CONTENTS. vii 



XIV. The ISlatural History of Oike tiens, a neti) and sin- 

 gular Genus of Lepidoptera. Bij the Rev. Lansdown 

 Guilding, jB.^. i^.L..S. - - - - p. 371 



XV. Observations on the Trachccc of Birds ; tcith Descrip- 

 tions and Representations of several not hitherto figured. 



By William Yarrell, Esq., F.L.S. - - p. 378 



XVI. On tzvo new Genera of Land Tortoises. By Thomas 

 Bell, Esq., F.L.S. Cominunicatcd by the Zoological 

 Club of the Linnean Society - - - p. 392 



XVII. Of the Insect called Oistkos by the Ancients, and 

 of the true Species intended by them under this Appel- 

 lation : in reply to the Observations of W. S. ]\Iac- 

 Leay, Esq., and the French ISaturalists. To xchich is 

 added, A Description of a nezi^ Species o/'Cuterebra. 

 By Bracy Clark, F.L.S., and Foreign Member of the 

 Rorjal Academy of Sciences of Paris - - p. 402 



XVIII. A Review of the Genus Combretum. By Mr. 

 George Don, A.L.S. - - - - p. 412 



XIX. Description of a new Genus of Plants belonging to 

 the Order Nymphaaceœ : in a Letter to H. T. Cole- 

 brooke, Esq., F.R.S., F.L.S. By Nathaniel Wal- 

 Mch, M.D., F.L.S., F. R.S.Ed. ,.^c. - - p. 442 



L Obsci'vations and Experiments, made with a view to 

 ascertain the Means by which the Spiders that produce 

 Gossamer effect their aerial Excursions. By John 

 Blackwall, Esq., F.L.S. - - - - p. 449 



XXI. De- 



