(4 to 6 times) longer than broad, about as long as two last abdominal segments; outer margin fringed with a row of fine teeth. Innermost tail setæ considerably longer than abdomen. Length 1/20 of an inch. Hab. Tomahawk lagoon, near Dunedin. My specimens are rather larger than the European form, but in all points of structure agree closely with Dr. Brady's description and figures. δ.—Anterior antennœ 8-jointed. 4. Cyclops chiltoni, n. sp. Pl. IX., figs. 11–19. Cephalothorax narrow-oblong in form, last segment hardly wider than abdomen; first segment three-fifths of the length of the whole; rostrum very short. Abdomen slender, subequal with cephalothorax in length, segments about as broad as long, surrounded by rings of minute comb-like teeth. Anterior antennæ three-fourths as long as the first segment of the body, rather stout, joints tapering to the extremity, first about four times as broad as the last; relative lengths as follows:— 1, 2, 3, 4, 5, 6, 7, 8,/18. 10. 7. 16. 7. 6. 11. 10. setæ tolerably numerous on the first four joints, last joint with 4 (sometimes 5 or 6, some very small) terminal setæ. Posterior antennæ large; the long seta on the basal joint almost smooth. Mouth organs very small. First four pairs of legs with strong spines. Fifth foot very small, 1-jointed (?), bearing 3 spines, the lower one of which is plumose. Caudal segments about 3 times as long as broad; central caudal setæ three-fourths as long as abdomen. Length, 1/18 inch. Hab. Numerous specimens obtained in gravel pits at Eyreton, by Mr. C. Chilton, after whom I have named it. Quite distinct from the two other species characterized by the 8-jointed anterior antennæ, viz., C. crassicornis, Müller, and C. magniceps, Lilljeborg. ε.—Anterior antennœ 6-jointed. 5. Cyclops œquoreus, Fischer. Pl. XI., figs. 16–18. Body gradually attenuated from before backwards. Anterior antennæ much shorter than first segment of thorax, stout at the base, and only slightly tapering towards the apex; 1st and 2nd joints stout, subequal, 3rd short, 4th the longest, 5th short, 6th about twice as long as 5th; the following represents the relative lengths of the joints in the majority of my specimens (females) 1, 2, 3, 4, 5, 6./10. 10. 5. 16. 7. 11. Mandibles dilated at the apex and divided into several slender sharp teeth. Maxillæ strongly toothed. Feet of the 1st pair short, and furnished with rather short setæ. Fifth feet bearing a triangular joint, dilated towards the extremity, and furnished with 3