308 A Rattlesnake in South Latitude 27°. 



practice. He also noticed that many birds build nests all the 

 year ; for example, gulls and goatsuckers. 



The class of reptiles appears not to have offered to M. d'Or- 

 bigny nearly so many subjects of observation as that of birds. 

 Every where indeed it is much more restricted both in species 

 and individuals. His catalogues do not extend beyond 119. 



From the inspection we have made of them, we perceive that 

 his collection contains several emydes or fresh- water tortoises, one 

 of which seems to be quite new : also several land tortoLses, of 

 which the T. carbonaria of Spix was a desideratum to our col- 

 lections. But there is no example of trionvx, or soft tortoise, none 

 of which seem to exist in tlie great rivers of Soudi America. M. 

 d'Orbigny has, however, often met with the ci-ocodile with bony 

 eyelids. 



In the division of Saurian reptiles, he has observed many 

 kinds of ameiva ; a species allied to the tropidolepis, or lizard 

 with spiny scales ; a second species of the genera doryphora 

 and opiums ; a new chalcidis, which, on account of the ease with 

 which its tail can be broken, the natives name acerilta, or steel 

 serpent, and which they regard, no doubt erroneously, as very 

 dangerous ; and, lastly, two distinct species, which may form a 

 generic group allied to Ecphimotes. 



In the division of Ophidians, some new species may likewise 

 be remarked, but of this it is more difficult to speak with as- 

 surance. M. d'Orbigny has never met with aquatic serpents, 

 which are so common in the Indian Seas ; but he has met with 

 a species of Crotalus or rattle-snake, as far as the 27th degree 

 south, becoming more common in the north, and some true 

 vipers. Of the fifty-two species of serpents which he has col- 

 lected, five or six only are poisonous. 



The class of Amphibia, judging from what M. d'Orbigny has 

 seen of it, is much poorer in those parts of America which he 

 has examined, than that of reptiles. Indeed he has met with 

 no examples, except an enormous toad, about a foot long, some 

 new species of frog, and of hyla ; but no terrestrial or aquatic 

 salamander, no siren, or other allied genera, which are so gene- 

 rally distributed over North America. Neither did he observe 

 any kind of pipa, or coccilido. 



But he has been more fortunate in the class of Fishes, particu- 

 larly fresh-water fishes, which were to be collected from all the 



