V.—Chemistry and Physics. Art. XLII. On the Regeneration of Cyanide Solutions. By Godfrey Doveton, M.A.I.M.E. Communicated by Professor J. Park 481–483 XLIII. Studies on the Chemistry of the New Zealand Flora. By Professor T. Easterfield and B. C. Aston 483–486 XLIV. Note on the Interaction of Citric and Sulphuric Acids. By James Bee 486–487 XLV. An Experiment bearing on the Wave Theory of Light. By J. S. S. Cooper 487–490 XLVI. The Physical Properties of Kauri-gum. By J. S. S. Cooper 490–492 XLVII. Note on a supposed Heat-effect. By J. S. S. Cooper 492 I.—Miscellaneous—continued. XLVIII. On certain Statistics respecting the Trend of English Trade. By Professor H. W. Segar 493–501 XLIX. A Note on Drawing for Competitions. By Professor H. W. Segar 501–504 L. A Comparison of the Age-distribution of the Populations of the Four Chief Provincial Districts of New Zealand. By Professor H. W. Segar 504–511 Annual Report of the New Zealand Institute 515 “New Zealand Institute Act, 1903” xii.–xiv. Regulations of the New Zealand Institute under the Act of 1903 xiv.–xvii. Report on Colonial Time-ball Observatory 517 Proceedings— Wellington Philosophical Society 523 " Auckland Institute 539 " Philosophical Institute of Canterbury 534 " Otago Institute 538 " Westland Institute 543 " Hawke's Bay Philosophical Institute 545 " Nelson 546

List of Plates at the End of the Volume. Plate To illustrate Article I. Calabash, with Carved Mouthpiece.—Newman I. II. Mouthpiece of Calabash.—Newman I III. Moriori Carving, Chatham Islands.—Hamilton III. IV. Veracity of Census Returns.—Segar VI. V. Veracity of Census Returns.—Segar VI. VI. Paryphanta fumosa.—Murdoch XVI. VII. New Zealand Sipunculids.—Benham XX VIII. Hirudo antipodum.—Benham XXI. IX. Regalecus parkeri.—Benham XXIII. X. Ixodes anatis.—Chilton XXIV. XI. Leaves of Panas simplex.—Cockayne XXVI. XII. Sand Dunes, Enderby Island.—Cockayne XXVI. XIII. Rata Forest, Auckland Island.—Cockayne XXVI. XIV. Olearia lyallii Forest, Ewing Island.—Cockayne XXVI. XV. Olearia lyallii Forest, Ewing Island.—Cockayne XXVI.