Rev. L. Guilding on Poli/brachionia Linnceana, 403 



rabbits. The ossicula auditus are considerably larger and much 

 nmore perfectly defined in form in our common Squirrel (Sciurus 

 vulgaris) than in the HareXL^pus timidus) notwithstanding the 

 great disproportion in the size of the two animals; the quantum 

 of power to collect vibrations of sound, depending on the form 

 and area of the conch, seems to explain this circumstance satisfac- 

 torily ; this smaller external part in the squirrel requiring a more 

 perfect internal construction and communication. 



Having stated that the auditory cells in the Fennec were larger 

 than those of our common Fox, the ossicula auditus as large in 

 proportion, and equally perfect in form, and the external conch of 

 great magnitude, as may be seen in the specimen of this very rare 

 animal in the Museum of the Zoological Society which has been 

 submitted to me for examination, it may be inferred, that its 

 powers of hearing are commensurate with the extraordinary de- 

 velopement of each particular part. 



The skeleton of the Fennec so closely resembles that of the 

 Dog as to make a particular description unnecessary; and there is 

 also one other point of similarity, the pupil of the eye is circular. 



W. Y. 



Art. XLI. Observations on the Zoologi/ of the Carihcean 

 Islands. By the Rev, Lansdown Guilding, B.A»y 



[Continued from Vol. ii. p. 444.] 



Radiata Caribeana. (No. 1.). 



Familia Porpitid^, Guild. 



Genus Polybuachionia,* Guild. Porpita, Lam. &c. 



Char, gener. 



Corpus orbiculare valde depressum, ad periphaeriam multi-ra- 

 diatum. 



* Nomen a vaXvs numerosus, et ^^oc^iuv brachium. 



2 c2 



