518 ME. E. I. POCOCK ON THE 



Odontopeltis mammatus, sp. n. (PI. XXXIX. figs. 8-8 h.) 



Allied to both the preceding. 



c?. Colour black, legs ferruginous. Slender, flat-backed. 

 Keels large and borizontal, formed almost as in O. formosus, but 

 ■« itb the posterior angle of the keels more produced and the whole 

 sculpturing much less like that of a genuine JBolydesmus ; the 

 upper surface of each segment adorned on each side with seven 

 mammiform excrescences, three of these along the posterior row 

 being more spiniform and directed backwards, especially the 

 external, which has the form of a large tooth at the point of 

 origin of the keel. 



Legs and antennce long. 



Cop ulat cry feet very short (as in figs. 8 «, 8 5). 



Length 17 mm. 



Localitij. Mandeville, Jamaica {T. D. A. CocTcerell). 



II. MALACOPODA oe PEOTOTEACHEATA. 



Any one versed in the problems of geographical distribution and 

 acquainted with the wide range, probable antiquity, and secluded 

 life of the species that have hitherto been included under the 

 genus Peripatus, would have been perfectly justified in con- 

 cluding from analogy that the species from each of the different 

 ref^ions would possess certain characters in which they would 

 resemble each other and differ from the species inhabiting the 

 other regions. 



That this is in reality the case is now an established fiict : for 

 the species from the Neotropical Eegion may be distinguished 

 from those from Africa and Australia, and those from the latter 

 two Eegious from each other, by both external and internal 

 characters ; or, to put it differently, the species fall into three 

 groups equivalent to, or indeed of considerably greater value 

 than, the genera of other orders of animals. 



Setting aside for the moment the less easily ascertained 

 characters, which may be found detailed in Prof. Sedgwick's 

 monograph, I propose to distinguish these genera by the fol- 

 lowing characters and names : — 



a. The legs furnished with four spinous pads ; the 



generative aperture in the adult always situ- ' 



ated between the legs of the penultimate 



