CONTENTS: 
I. Description of the Organ of Voice in a new Species of Wild Swan (Cyg- 
nus Buccinator, Richardson). By Wiiutam YarreLL, Esq., F.L.S. & 
Mal do MB es e o’ ro orne page 
II. Descriptions of three British Species of fresh-water Fishes belonging to 
the Genus Leuciscus of. Klein. By Witttsm Yarrew, Esq., F.L.S. & 
III. Observations on the Tropæolum pentaphyllum of Lamarck. By Mr. 
BoA ON, HM IAS. (Cx ee re SW 
IV. On the Adaptation of the Structure of the Sloths to their peculiar Mode of 
Life. By the Rev. Wiut1am Bucxiann, D.D., F.R.S. F.L.S. F.G.S., 
and Professor of Geology and Mineralogy in the University of Oxford. 17 
V. Observations on Naticina and Dentalium, two Genera of Molluscous Animals. 
By the late Rev. Lanspown Guine, B.A., F.L.$. . . . . . 29 
VI. Monograph of the East Indian Solanee. By Curistian Goprrey NEES 
von EskNBECK, M.D., F.M.L.S., President of the Imperial Academy 
Nature Curiosorum, and Professor of Botany in the University of Bres- 
Ml i eo. ec? sage, See n 8f 
