662 LIEUT.-COL. H. H. GODWIN-AUSTEN ON [DeC. 14, 



Eepreseutative Groups. 



Stages of Evolution. , * ^ 



9. Eutkcria Monodclphia. 



O 



8. Metathcrkh Marsiipialia. 



O 



7. Trototheria Monotremata. 



O 



6. Hypotheria X Saurojpsidci ,. \ t^^^I-j- 



5. Amphibia Aiiipfiibia X 



O 



i. Hcrpetichihi/es... Dipnoi X ... Osteichthi/cs..J ^Z,"'l""'f'' 



3. Ckondrichtht/cs.. Chimmroidci X ... X 



O 



Selachii. X ... X 



O 



2. Myzichthyes ... Marsipobrajickii ... X ... X 



O 



1. Hypichtliijcii ... PkaTyngobranchii... X ... X 



O 



It appears to me that every thing which is at present known 

 respecting the Vertebrata of past epochs agrees with the assumption 

 that the law which expresses the process of ancestral evolution of the 

 higher Mammalia is of general application to all the Vertebrata. If 

 this is admitted, I think it necessarily follows that the Vertebrata 

 must have passed successively through the stages here indicated, and 

 that the progress of discovery, while it will obliterate the lines of 

 demarcation between these stages, and convert them into a con- 

 tinuous series of small differentiations, will yield no vertebrate 

 form for which a place does not exist in the general scheme. 



2. On the Anatomy of Ferussacia gronoviana, Risso, from 

 Mentone. By Lieut. -Colonel H. H. Godwin-Austen, 

 F.E.S., F.Z.S., &c. Concluding with a Note on the 

 Classification of the Genus and its Allies, by Geoffrey 

 Nevill, C.M.Z.S. 



[Eeceired November 22, 1880.] 



(Plate LXIV.) 



In a communication made to this Society last year (P. Z. S. 188(', 

 p. 133), Mr. G. Nevill's paper on the Land Shells of Mentone, I 

 alluded, in a footnote, to having had an opportunity of examining the 

 animal oi Ferussacia gronoviana, which Mr. Nevill had brought home 

 alive ; the promised details are now given. The animal apparently, 



