Art. I.—Notes on the Skeleton and Baleen of a Fin-whale (Balænoptera musculus?) recently acquired by the Otago University Museum.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 17, 1884, Unnumbered Page

Art. I.—Notes on the Skeleton and Baleen of a Fin-whale (Balænoptera musculus?) recently acquired by the Otago University Museum. By T. Jeffery Parker, B.Sc. Lond., Professor of Biology in the University of Otago. [Read before the Otago Institute, 14th October, 1884.] Plate VI Rather more than a year ago, a large whale's skeleton was exhibited in many parts of the colony by Captain Jackson Barry, who finally brought it to Dunedin. On visiting the shed where the bones were roughly set up, I found the animal to be a Balænoptera, a genus hitherto not represented in this Museum; and, as the number of bones missing was comparatively small, and the baleen was perfect, I entered into negotiations with Mr. Barry, with the ultimate result of securing the specimen as soon as it had ceased to “draw” as a show. In one of his valuable contributions to our knowledge of the Cetacea,* “On a Lesser Fin-whale recently stranded on the Norfolk Coast.” Proc. Zool. Soc., 1864, p. 252. Professor Flower remarks: “We have at present so little definite information upon the specific characters and geographical distribution of the Cetacea, that it is desirable that no opportunity should be lost of putting on record any facts which may contribute to the better knowledge of the natural history of even the most common species of this interesting group of Mammalia.” I have, therefore, thought it advisable to communicate to the Institute a few notes on the specimen in question, with a view of furnishing a series of measurements for comparison with those already on record, and of calling attention to one or two points in which the specimen differs from hitherto described examples. It also seems desirable that an accurate account of the skeleton as it reached the Museum should be placed on record, so that any one interested in the matter may have no difficulty in finding out at once how far the specimen, as mounted, is “restored.”

The whale, as I am informed by Mr. J. E. Gully, was stranded on the sands at the entrance of the Waimea River, Nelson. It was boiled down, and the skeleton and baleen passed into the possession of Captain Barry, who unfortunately was not sufficiently aware of the value of a complete whale's skeleton to give the proper amount of care to the preservation of the smaller bones. The eight (?) posterior caudal vertebræ were thrown away with the “flukes;” the anterior epiphysis of the fifth cervical vertebra is missing; many of the phalanges and some of the carpals are lost; and no trace of either pelvic bone reached Dunedin.* I am much indebted to Mr. J. E. Gully for having instituted a search for the missing bones, but unluckily his efforts met with no success. The rest of the skeleton is quite perfect and in excellent condition. The small fifteenth rib is present on both sides, as well as the lacrymal and the malar. The hyoidean apparatus is complete, and the number of chevron bones (13) agrees with Van Beneden and Gervais's figure of B. musculus, although from the description of that species in the “Ostéographie des Cétacés” it seems probable that these were followed by three others in the cartilaginous condition. The skeleton is in the stage defined by Flower† “Notes on the Skeletons of Whales in the Principal Museums of Holland and Belgium, etc.,” Proc. Zool. Soc., 1864, p. 384. as “young,” that is, all the epiphyses both of the vertebræ and of the arm bones are separate. The bones of the skull also shrunk away from one another a good deal in the course of drying, so that it was found impossible to bring them into contact. This is especially the case with the maxillæ and the orbital processes of the frontals, between which there is a gap of about two inches. The premaxillæ and maxillæ were both separated during the preparation of the skull, as well as the lacrymals and jugals. The entire length of the skeleton, as mounted, is 53 feet 6 inches, measured in a straight line. This includes eight restored vertebræ at the end of the caudal region, as well as the pads of felt representing inter-vertebral ligaments: the latter vary from ½ to ⅞ inch in thickness in different parts of the vertebral column. This size appears to be somewhat remarkable for so young a specimen. Flower states that whales grow to more than half the size of the adult while still in the “young” stage, but it is certainly interesting to find a length of over 54 feet attained in the young stage of a species which appears never to exceed 80 feet, and in which the fully adult condition of the skeleton may be reached in specimens of 70 and even 60 feet long. The following measurements are taken to correspond pretty nearly with those given by Flower‡ P.Z.S., 1864, p. 399, etc. and by Murie,∥ “On the Anatomy of a Fin-whale captured near Gravesend,” Proc. Zool. Soc., 1865, p. 206. and will help to show the close

correspondence in the proportions of the various parts of the skeleton, between the present specimen, and acknowledged examples of Balænoptera musculus (=Physalus antiquorum). The Skull. Inches. Length in a straight line 148 Breadth at the squamosals (greatest breadth of skull) 68 " of condyles 13 ½ " of exoccipitals 47 ½ Length of supra-occipital 80 " of orbital process of frontal 26 Breadth " " ", at base 29 ½ " " " ", at outer end 15 ½ Length of nasal 11 Breadth of both nasals, posterior end 4 ½ " " " anterior " 9 ½ Length of beak from middle of curved border of maxilla to tip of premaxilla 102 ½ Length of maxilla 113 Projection of premaxilla beyond maxilla 10 Greatest width of nasal apertures 14 Breadth of both maxillæ at posterior end 15 " " " " "across orbital process (following the curve) 73 " beak at base, following the curve 54 " " middle " " 26 ½ " maxilla at same point " 8 ⅝ " premaxilla " " 4 Length of mandible in a straight line 144 Height of " at coronoid process 15 ½ " " at middle 10 ¼ Amount of curve of mandible, i.e., greatest distance of inner surface from a straight line between the ends 18 ¾ Length of jugal in a straight line 12 ½ Width of jugal at anterior end 6 " " posterior " 2 " " narrowest point 1 ¼ Amount of curve of jugal (measured as for mandible) 2 ¼ Length of lacrymal in a straight line 9 ½ Greatest breadth of lacrymal 3 ¾ Length of tympanic5 ½ " " including external process 13 Breadth " 4 ¾ Thickness " 2 ½ The Hyoid Bone. Extreme width in a straight line 28 Length of body from posterior edge to fork of anterior cleft 5 ¼ " " " " " extremity of anterior corner or process for articulation of stylo-hyal 8 Breadth of body, about 6

Inches. Length of stylo-hyals 15½ Greatest breadth of stylo-hyals 3½ " thickness of " 2 " breadth of thyro-hyals 4 " thickness of " 3¼ Breadth of thyro-hyals at proximal end 3¼ Thickness " " " 2½ Breadth " distal " 1¾ Thickness " " " 1¾ The Vertebral Column.— Vertebral Formula:—C. 7: Th. 15: L. 15: C. 17 + 8 (?)=62 (?). Dimensions in inches. of Body. of Neural Spine. of Transverse Process. of Foramina of trans. process. of Neural Canal. of Metapophyses Greatest Height. Greatest Width. Height Width Thickness Length Greatest width Length Greatest width (vertical) Greatest breadth (antero-posterior) Greatest height Greatest width Height. Width. Height. Width. Height of Hypapophyses. Cervical Vertebræ— I. 14 ½ 22 3 14 3 3 4 3 ¾ 5 8 5 II. 14 ½ 27 9 ½ 14 3 2 4 ½ 8 11 3 5 ¾ 5 ½ 6 ½ III. 12 ½ 25 7 ½ 12 1 ½ 1 2 7 ½ 10 ¾ 7 7 5 7 IV. 12 ½ 25 7 ½ 11 ½ 1 ¾ 1 ½ 1 ½ 7 10 6 ½ 6 4 8 V. 12 ¾ 25 7 ½ 11 1 ¾ 1 ¾ 1 ½ 7 ½ 10 6 ½ 6 ½ 3 ½ 8 VI. 13 ½ 26 7 ½ 11 2 ½ 2 1 ¾ 8 10 ½ 6 ½ 6 ¾ 3 ½ 8 ¼ VII. 14 25 7 ½ 11 3 2 ½ 1 ¾ 8 3 3 ½ 8 ½ Thoracic Vertebræ— I. 15 25 7 ¾ 11 3 3 ¾ 2 ½ 7 ½ 5 3 ½ 8 ½ III. 18 25 7 ¼ 12 5 6 ¼ 5 9 ½ 7 5 7 ¾ V. 21 31 7 11 ½ 6 ¾ 8 ½ 7 11 6 6 6 ½ 1 ¾ 4 VII. 23 34 7 ½ 11 7 ½ 10 8 11 ½ 7 6 5 1 4 IX. 23 ½ 35 7 ½ 11 8 10 ½ 8 12 7 ½ 5 ½ 4 ½ 1 ½ 4 ½ XI. 24 36 7 ½ 11 ½ 8 ½ 10 ¾ 7 ½ 12 7 ½ 4 ¼ 4 ¼ 2 4 ¾ XIII. 24 ½ 37 8 12 8 ½ 11 7 ½ 12 7 5 5 ¾ 2 4 ½ XV. 25 34 8 ½ 12 9 11 ½ 7 ½ 11 ½ 5 ½ 5 ¼ 3 ½ 2 4 Lumbar Vertebræ— II. 26 34 8 ½ 11 ½ 9 13 7 ½ 11 6 5 ½ 3 ½ 2 ¼ 4 ½ IV. 26 ½ 35 9 12 9 ¼ 12 ½ 7 11 6 4 ½ 4 2 4 ½ VI. 27 34 9 ½ 12 ½ 9 ½ 13 ¼ 7 12 7 4 ½ 4 2 4 ½ VIII. 27 ½ 33 ½ 9 ½ 12 ½ 10 14 ½ 6 12 7 4 4 ¼ 2 ½ 4 ½ X. 27 ½ 34 10 12 ½ 10 14 ½ 7 11 6 ¾ 4 4 2 ¼ 4 ¼ XII. 27 33 10 ½ 13 10 ½ 14 ½ 7 ½ 10 7 4 3 ¾ 2 ¼ 4 ¼ XIV. 27 32 10 ½ 13 11 13 8 9 ½ 6 ¾ 4 ¼ 3 ½ 1 ½ 3 ¾ Caudal Vertebræ— I. 27 ¼ 28 11 ½ 13 ½ 11 ½ 12 7 ½ 7 7 4 ¾ 3 ¼ 1 ¼ 3 ½ ¾ III. 27 26 11 ½ 13 ½ 11 ½ 10 ½ 6 ½ 6 ½ 6 ½ 4 3 1 ¼ 2 ¾ 1 V. 22 ¾ 24 12 13 ½ 11 ½ 6 ¾ 5 5 5 3 ¼ 2 ¼ 1 ½ 3 1 ¼ VII. 20 ¼ 19 12 14 11 ½ 5 3 ½ 2 ½ 6 2 ½ 2 1 ¾ 2 ½ 1 ¾ IX. 17 ½ 16 12 13 11 4 2 ½ 2 6 2 1 ½ 1 ½ 3 ¼ 2 XI. 16 ½ 14 11 11 ¾ 11 2 ¼ 1 ½ Reduced to mere ridge 1 ¼ 1 ¼ 1 ½ 2 ½ 2 XIII. 12 ½ 11 10 ½ 10 9 ½ 1 1 1 1 1 ¼ 2 ½ 2 ½ XV. 10 8 ½ 8 8 ½ 6 ½ XVII. 7 6 ¾ 7 6 ¾ 4 ¾

The Chevron Bones.— Greatest height (vertical). Greatest breadth (antero-posterior). I. 6 ½ 3 inches. II 10 5 ½ " III. 10 ½ 5 ½ " IV. 10 ½ 6 " V. 10 ½ 7 " VI. 10 7 ½ " VII. 9 ½ 7 ½ " VIII. 9 6 " IX. 8 ½ 6 " X. 7 ½ 5 " XI. 6 ½ 5 " XII. 5 5 " XIII. 4 3 ½ " The Ribs.— (Left side. Dimensions in Inches. Greatest length, following outer border of arch. Greatest length in a straight line. Diameter of chord. Greatest breadth of head. Breadth of neck. Breadth at middle or rib. Breadth of fin point. I. 45 40 ¾ 8 ¾ 5 ¾ 4 ½ 4 ½ 6 ¾ II. 65 59 12 ½ 8 ¾ 4 ¾ 4 4 ¾ III. 77 68 15 8 ¾ 4 3 ½ 3 ½ IV. 83 70 16 ¾ 5 3 ½ 3 ¼ 3 ¼ V. 86 72 ½ 18 4 ¼ 2 ¾ 2 ¾ 3 ¼ VI. 87 72 19 3 ¾ 2 ½ 2 ¾ 2 ¾ VII. 87 72 17 ¾ 3 ½ 2 ¼ 3 3 VIII. 83 ½ 69 16 ¼ 3 ½ 2 ¼ 2 ¾ 2 ½ IX. 78 ½ 66 ½ 15 3 ¼ 2 ¼ 2 ½ 1 ¾ X. 72 63 ½ 13 ½ 3 ½ 2 2 ¼ 1 ¾ XI. 67 60 12 3 ¼ 2 2 1 ¾ * These ribs have apparently had the distal end out off, so that the measurements are probably not strictly accurate. XII. 62 57 9 2 ¾ 2 2 1 ¼ * These ribs have apparently had the distal end out off, so that the measurements are probably not strictly accurate. XIII. 57 55 6 ½ 3 1 ¾ 2 ¼ 1 ¾ * These ribs have apparently had the distal end out off, so that the measurements are probably not strictly accurate. XIV. 60 57 ½ 7 2 ½ 1 ¾ 2 ¼ 2 XV. 25 24 ½ 1 ½ 2 1 ½ 1 ½ ¼ The Sternum.— Inches Greatest length .16 ½ " breadth 13 ½ The Scapula.— Greatest breadth in a straight line between the angles of the supra-scapular bridge 38 Length to the glenoid cavity 24 " of coracoid 3 ½

Breadth of coracoid at bas 3 Length of acromion 8 Greatest width of acromion 3 ¾ Antero-posterior diameter of glenoid cavity 9 ¼ Transverse 6 ¾ Circumference of glenoid cavity 25 The Humerus.— Greatest length 17 Greatest breadth at head 9 ¼ Greatest breadth at narrowest part of shaft 6 ¾ Greatest breadth at condyles 9 ½ Circumference of neck 27 Circumference of middle of shaft 18 ½ The Radius.— Greatest length 29 Breadth of head ½ Circumference of head 17 Diameter at middle of shaft 4 ¼ Circumference at middle of shaft 11 ½ Diameter of distal end of shaft 6 Circumference 16 The Ulna.— Greatest length 29 ½ Length of shaft 26 ½ Circumference of shaft at neck 11 Diameter of shaft at middle 3 Circumference of shaft at neck 8 Width of distal end 5 Circumference of distal end 12 Length of olecranon, taken parallel to shaft 7 It would be quite superfluous to enter into any detailed description of the skeleton, the correspondence with published accounts of Balænoptera musculus of the Northern Hemisphere being so close as, in most respects, to amount to identity. Indeed, with one or two trifling alterations, many of Van Beneden and Gervais's figures of that species∗∗ Ostéographie des Ætacés. might have been taken from the present specimen. There are, however, one or two points in which the skeleton appears to differ from those hitherto described. 1. The Nasals (fig. 1).—In these the anterior processes are unusually large, and the bones are altogether larger in proportion to the skull than is usual in B. musculus. For instance, in the Alexandra Park skeleton, with a skull 38 inches longer than that of the present specimen, the nasals are four inches shorter, the same width at their posterior ends, and two inches

Balænoptera Musculus.

narrower at their anterior ends. Judging from published figures also, the upper surfaces of the bones seem to be unusually strongly ridged. Each has a prominent ridge along its inner border, then a somewhat triangular depression with forward apex, then a strong oblique ridge passing from about the middle of the posterior border of the bone to its antero-internal angle; from the outer edge of this ridge the bone slopes downwards, ending externally in a low ridge. 2. The Jugals (fig. 3).—I have not succeeded in finding any special description or figure of the jugal; but, judging from the appearance of the bone as shown in Van Beneden and Gervais's figures of the skull of B. musculus,* Op. cit., pl. xii. and xiii., figs. 11 and 12. that of the present specimen appears to be broader at its anterior and narrower at its posterior end, than usual, and to be somewhat strongly curved. Owing to the absence of separate figures of this bone and of the lacrymal (fig. 2), in the works at my disposal, I have thought it advisable to give figures of both, drawn to the same scale as the nasals. 3. Breadth of Beak.—The proportion of the breadth of the beak to the length of the skull seems to be smaller than usual, being as 17.5 : 100. In six skeletons measured by Flower, the proportion varies from 18 : 100 to 21 : 100. 4. Vertebral Column.—The places at which the various dimensions of the vertebræ reach their maximum, differ slightly from those recorded by Murie in the Rosherville Gardens specimen,† P.Z.S., 1865, p. 206. and the relative dimensions of the vertebræ themselves show certain differences, but I do not consider these of sufficient importance to be recorded, except in the table of measurements. 5. The Sternum (fig. 4).—This differs from the corresponding bone in all the skeletons of B. musculus of which I have seen descriptions, in being longer than broad, like that of B. rostrata. The length is to the breadth as 16 : 18, while, in other specimens measured, the proportion is about 16 : 20. The antero-lateral edges and the lateral angles were, however, evidently edged with cartilage, so that the breadth was probably considerably greater in the fresh state. Van Beneden and Gervais give the excess of breadth over length in B. musculus as a character of specific importance. Von Haast also figures the sternum of B. australis, which he seems to think is probably identical with B. musculus, as broader than long,‡ “Notes on New Zealand Whales,” Trans. N.Z. Inst., vol. vii., 1874, p. 251. and the same is the case with a specimen of the same species described by Hector.∥ “Notes on a Skeleton of Balænoptera australis, etc.,” Proc. Zool. Soc., 1883, p. 592.

6. The Fore-limb.—The humerus is but slightly compressed, and cannot be said to have a sharp lower (pre-axial) edge as described by Van Beneden and Gervais, who also state that the ulna and radius are twice the length of the humerus. In the present specimen the length of the humerus is to that of the fore-arm as 3 : 5 (strictly as 17 : 29). The total length of the fore-limb, as mounted, from the head of the humerus to the tip of the second digit, is 6 feet 2 inches. The Baleen (fig. 5). The baleen was cut into about six pieces on each side, but the separate portions appear to be as nearly perfect as possible. The total number of blades on each side—about 350—corresponds exactly to the number found by Flower* “Notes on four specimens of the common Fin-whale,” Proc. Zool. Soc., 1869, p. 604. in an entire specimen of Balænoptera musculus obtained near Havre. In the middle of the series I find 39 plates to a foot; Flower gives this number as 24. The length of the anterior blades is about 6 inches: the longest are 23 inches measured along the outer edge, 30 inches along the inner edge, and 10 ¼ inches along the base or dorsal edge. In Flower's Havre specimen the anterior blades were 7, the longest 21 inches in length, the total length of the specimen, in the flesh, being 61 feet. The anterior blades are yellowish white, the rest slate-coloured, with irregular vertical stripes of pale horn-colour, especially numerous towards the inner edge. The whole of the fibres forming the inner surface of the baleen are nearly white; they attain a length of 11 inches in the middle of the series. There is a distinct inner fringe formed by the dorsalmost fibres, which are about six inches in length: it seems just possible that this inner fringe may be due to a uniform longitudinal splitting of the blades during drying. There is no trace of the curled fibres described by Flower in the Havre specimen† P.Z.S., 1869, p. 604. as occurring on the outer side of the hindmost plates. It will be seen that the agreement with Balænoptera musculus is here very close, except in the number of blades to a foot in the middle of the series. I am disposed to wonder whether the number given by Flower (24) is not a misprint, since if the distance between the blades through the whole series were anything like uniform—as it is in my specimen—the total antero-posterior extent of the baleen would be nearly 15 feet, whereas the total distance from the end of the muzzle to the middle of the eye is given as 12 feet. If the number 24 is correct, the blades in the Havre specimen must have been much crowded at either the anterior or posterior end of the series, or both.

The foregoing observations show that the present specimen agrees with Balænoptera musculus in every essential respect except the characters of the nasals and of the sternum. Without knowing anything of the external characters I think it would be extremely injudicious to consider the peculiarities of these bones as having anything more than a varietal importance. Indeed one would have no hesitation in definitely referring the Nelson skeleton to the same species as the common Rorqual of the northern hemisphere, but for the fact that considerable confusion seems to exist as to the external characters of the Southern Fin-whales. In a recent article* Encyclopædia Britannica, 9 ed., vol. xv., art. Mammalia. Professor Flower remarks: “There are certainly four quite distinct modifications of this genus [Balænoptera], represented by the two just mentioned [B. sibbaldii and B. rostrata], and by B. musculus and B. borealis, all inhabitants of British seas; but the question whether almost identical forms found in the Southern or Pacific Oceans are to be regarded as specifically identical or as distinct, awaits the result of future researches.” Gray† Catalogue of Seals and Whales, p. 161. describes a species, Physalus? (Balænoptera) australis, Desmoulins, distinguished by having the dorsal fin over the male organ as in Megaptera. The same author‡ Loc. cit., p. 164. admits a species, Ph. antarcticus, founded entirely upon some yellowish-white baleen imported to England from New Zealand. Hector∥ Trans. N.Z. Inst., vol. vii., p. 251. calls the Port Underwood skeleton Physalus australis in the text of his paper, while in the description of plates it is referred to as Ph. antarcticus. Taking into consideration that it is an adult skeleton, it agrees in all essential respects with the Nelson specimen, at least as far as I can judge from the brief description, except in the form of the sternum, which, as stated above, is broader than long. It was upon the Port Underwood skeleton that Gray§ Note to paper by Hector, Ann. and Mag. N.H., 4 ser., vol. xiv., 1874, p. 304. founded his new genus and species Stenobalæna xanthogaster “peculiar for the shortness of its pectoral fins, its plaited belly, and low recurved and pointed fin placed over the vent, and very peculiar among all whalebone-whales for the form of its bladebone.” As a matter of fact, I find on referring to Hector's paper that the pectoral fin was only a little less than one-eighth the total length of the body (body 70 feet, bones of fore-limb 8 feet 6 inches), which appears to be the usual proportion for B. musculus: the plaited ventral surface also obtains in that species, in which, further, the dorsal fin is over the vent. As for the scapula, all Dr. Gray had to depend on was an extremely rough sketch taken from the fresh bone before the cartilage was removed, and apparently

very much foreshortened: as Dr. Hector remarks, it is not like the macerated bone, which has all the characters of the scapula of B. musculus. So that, on examination, there seem to be positively no definite characters upon which the Port Underwood whale can be separated from B. musculus. This is evidently Dr. Hector's opinion,* “Notes on the Whales of the N.Z. Seas,” Trans. N.Z. Inst., vol. x., p. 336. although he still adheres to the name B. australis. In Haast's New Brighton† P.Z.S., 1883, p. 592. specimen the position and form of the dorsal fin were unfortunately not ascertained; in every other respect the agreement with B. musculus is quite close. There seems therefore to be, as far as the information at my disposal goes, complete specific identity between at least two well-authenticated specimens of the Southern Rorqual and its northern representative. And it would further appear that in every respect in which the Nelson specimen differs from B. musculus, it also differs, and in the same manner, from the so-called B. australis. On the whole it seems to me that one is justified in assigning the present specimen, as well as the Port Underwood and New Brighton specimens, to Balænoptera musculus, at least until the accurate examination of both external and internal characters in the same individual has definitely proved the existence of a distinct species of Southern Rorqual. In the skeleton as mounted the intervertebral ligaments are represented by pads of felt, and the following missing bones by wooden models:— The eight posterior caudal vertebræ (18th–25th). The three posterior chevron bones (14th-16th). Both pelvic bones (modelled from Haast's figure of the pelvis of the New Brighton specimen). In the right manus The 1st phalanx of the 2nd digit. The 4th and 5th phalanges of the 3rd digit. The 1st, 3rd, and 5th phalanges of the 4th digit. The 2nd and 3rd phalanges of the 5th digit. In the left manus The 5th phalanx of the 3rd digit. The 1st, 3rd, and 5th phalanges of the 4th digit. The 2nd and 3rd phalanges of the 5th digit.

The cartilaginous portions of the anterior cornua of the hyoid are restored, but the sternal ribs are entirely omitted, as I can find no figure of them, except one of Turner's,* Journ. of Anat. and Phys., vol. 4, 1870, p. 273. showing the relations of the first sternal rib to the sternum in Balænoptera sibbaldii. Only one complete set of carpals could be made up. Each of these was divided tangentially, and half used for each manus by being partially imbedded in the cement used to represent the continuous carpal cartilage. The skeleton is suspended in the centre of the Museum from girders of railway-iron passing between the capitals of the columns supporting the upper gallery. I am greatly indebted to Mr. W. N. Blair, C.E., Engineer-in-charge for the South Island, for having kindly furnished me with an extremely suitable design for these supports. The articulation of the skeleton has been very successfully done by my second assistant, F. J. Bourne, who also designed the whole of the ironwork, with the exception of the girders. I have to thank my friend and colleague Professor Scott, M.D., for having made the drawings from which figures 1, 2, and 3 are taken. Explanation of plate VI Fig. 1. The nasals, dorsal aspect. Fig. 2. The left lacrymal, posterior aspect. Fig. 3. The left jugal, ventral aspect. Fig. 4. The sternum, dorsal aspect. Fig. 5. One of the longest plates of baleen.