'474 MR. n. I. pococK ok the 



copulatory feet on the 7tli segment, and the incompleteness of 

 the anal segment. 



The collector, Mr. H. H. Smith, may also be congratulated 

 upon the discovery oiPolyxenus, which is new to the Neotropical 

 Fauna. The genus Siphonotus, too, which has been long lost 

 sight of, is worthy of special mention. 



These three forms are all of very small size, and they may be 

 taken as probably a fair criterion of what may yet be accom- 

 plished in this group if collectors will pay attention to the 

 minute as well as the more striking species. 



In the present state of our knowledge of the Neotropical 

 Diplopod fauna, it is impossible to enter into a detailed com- 

 parison between that of the Antilles and of any other area of 

 the Eegion. As a rule the species of this group are very 

 restricted in range. This is well shown in the present instance 

 by the fact that in only one or two cases is a species found 

 beyond the limits of a single island. Thus in the case of 

 Dominica, St. Yincent, Santa Lucia, and Grenada, with the 

 Diplopod fauna of which we may now perhaps consider ourselves 

 fairly well acquainted, it is noticeable that each seems to have its 

 peculiar species of Hhinocricus. In Dominica, JR. leucostigma is 

 very abundant ; in St, Vincent B. macropus and R. vincentii alone 

 occur ; while in Santa Lucia many species were found which did 

 not extend to the neighbouring islands. Most of these species, 

 however, are obviously very closely related to each other, and 

 they belong to a group which is apparently rather characteristic 

 of the northern parts of S. America. 



Class PSELAPHOaNATHA. 

 Family Poltxekid^. 



POLTXENtrS LONGISETIS, sp. n. (PI. XXXVII. fig. 1.) 



Colour (in alcohol) pale ; the setse greenish. 



The body slightly attenuated posteriorly, with 10 dorsal 

 plates visible between the head and the posterior tul't of setae, 

 the last plate narrower than the preceding one and sometimes 

 appearing to be concealed inside it. 



The antennae very long, projecting on each side far beyond 

 the sides of the body; the setae on the lateral processes very 

 long ; the posterior tuft of setae much narrower than in 

 P. lagurus. 



