413 Bihliography. 



on their natural history, derived mostly from Dr. Savage, by whom they 

 were brought from the western coast of Africa. Dr. Harris has here 

 described the female of Mecynorhina Polyphemus, which was not 

 known until brought to notice by Dr. S., and institutes a new species 

 under the name of Mecynorhina Savagii, from male and female spe- 

 cimens derived from the same source. 



" The importance of habit as a guide to accuracy in systematical ar- 

 rangement, illustrated in the instance of the Sylvia Petechia of Wilson, 

 &c., by T. McCuLLOcH, Jr., of Halifax, Nova Scotia." The author of 

 this paper takes a very just view of the insufficiency of external char- 

 acters alone for the accurate discrimination of allied species, and insists 

 upon an acquaintance with internal structure, stating also that in its 

 absence, habit may sometimes serve as a guide in finding the true place 

 of a species. Apart from the main object of the paper, which is well 

 sustained, the observations of the author upon the Sylvia Petechia form 

 a valuable supplement to the history of this species. 



" On the anatomy of Telennophorus Carolinensis,'''' and " on the 

 anatomical structure of Glandina truncata^'' two papers by Jeffries 

 Wyman, M. D. The object of these papers is to show that the inter- 

 nal structure of these animals, justifies their separation from the genera 

 in which they have hitherto been repeatedly placed, and their institu- 

 tion as the type of distinct genera. Tehennophorus was founded on the 

 animal described by Bosc as Limax CaroUnensis, and unless all the 

 naked slugs are to be included under one genus, we cannot doubt the 

 propriety of its adoption. The details of its structure vary consider- 

 ably from those of any other genus. So too with Glandina truncata, 

 both externally and internally it differs as much from every other genus, 

 as any two do from each other ; and the possession of a third pair of 

 tentacles stamps it with a marked peculiarity. 



" Description and habits of some of the birds of Yucatan," by Sam- 

 uel Cabot, Jr., M. D. p. 460. Dr. Cabot accompanied Messrs. Stevens 

 and Catherwood in an expedition to Yucatan, and the present remarks 

 are among the results of his observations. He gives some particulars 

 of the habits of Ortyx nigrogularis of Gould, and an extended descrip- 

 tion of the female, which was not seen by the latter. Dr. Cabot brings 

 forward as new to science, four species of birds, of which he gives full 

 descriptions, taken both from males and females, with notices of their 

 habits, and an account of some of his own adventures when procuring 

 them. The species proposed are Falco Percontator, Corvus vociferus, 

 Oriolus musicus, Momotus Yucatacensis. 



" Enumeration of the recent fresh-water mollusca which are com- 

 mon to North America and Europe ; with observations on species and 

 their distribution," by S. S. Haldeman. The species supposed to be 



