392 DESCKIPTION OF A MITE 



UrOPODA FORMICARI.E, sp. nov. 



This species, although it falls strictly within the 

 genus Uropoda, and not within Kramer's genus 

 Trachynotus as defined by that writer, still in most 

 respects, except the very distinctions upon which the 

 genus is founded, resembles Trachynotus pyriforTnis 

 ( Kramer) more closely than it does any other recorded 

 species. It is, however, decidedly different, and is 

 characterised by the squareness of its abdomen, the 

 thickness and roughness of its chitinous dermal skele- 

 ton, and especially by the powerful chitinous ridges or 

 wing-like expansions on the lateral surface between the 

 second and third pair of legs. 



Length, ^ and ? , about "95 millim. 

 Breadth „ „ '55 „ 



The abdomen is almost square, but somewhat longer 

 than broad, and slightly narrowed at its junction with 

 the cephalothorax, from which it is not plainly dis- 

 tinguished. The extreme edge is a strong chitinous 

 ridge bordered with a thick fringe of short, stout, 

 curved hairs, as in T. pyriformis. The dorsal surface 

 of the cephalothorax is also narrowed towards the front, 

 and has a curved anterior margin bent down so as to 

 protect the mouth, as in that species ; it bears a few 

 of the same kind of hairs as the abdomen, and has a 

 chitinous thickening at each side. The abdomen rises 

 almost perpendicularly from the marginal ridge. There 

 is a central depression occupying the posterior half, or 

 rather more than half of the abdomen ; and at the bottom 

 of this depression are transverse ridges, the hinder ones 

 nearly straight, and the anterior ones bent in the 

 middle, the central point being forward ; at the sides of, 

 but not in, this depression, are two chitinous blocks 

 which seem to form a starting-point for the ridges 

 Anterior to this depression the central portion of the 



