10 T. V. HODGSON. 



single joint and about one-third the length of the entire appendage is present. Its 

 apex is provided with a few long setse. The epignath is very small and ovoid. 



The appendages of the mesosome show a transition between the subchelate first 

 and the more locomotive posterior ones. The first of these appendages (fig. le) is 

 stoutly built, the basis is a little longer than the ischium. The merus is a peculiar 

 joint and is short, very much expanded dorsally to embrace the base of the propodus ; 

 it bears several long setse ventral! y and two or three at the dorsal extremity. 



The carpus is a small joint, on the inner side of the appendage, apparently 

 wedged in between the merus and the propodus. Internally it forms a thin, roughly 

 rectangular plate, rather than a joint, which carries a few setse and a couple of spines. 

 The propodus is large, rather flask-shaped, with its inner margin expanded as a thin 

 plate ; this expansion has a thumb-like process at the inner extremity, and is armed 

 near its anterior border with a row of small but highly specialised spines. The 

 joint is attached near its middle to the carpus, the rounded base being adapted to 

 the crescentic enlargement of the preceding joint. 



The specialised spines are about a dozen in number and are set in distinct sockets, 

 and a long seta is associated with each. The structure of the spine is difficult to make 

 out, but appears to consist of a stout shaft with a group of stout teeth on one side. In 

 some cases one or two teeth are to be seen on the other side of the shaft, but much 

 nearer its base. I have not deemed it desirable to injure the appendage in order to 

 examine these spines more minutely. The dactylus is long and curved, set at the 

 external angle of the propodus, and it carries on its inner margin a small number of 

 widely separated setse. 



The second appendage (fig. If) is similar to the first in general structure, the basis 

 is, however, proportionately longer and more slender, the merus and other joints are 

 also smaller, and the expansion of the propodus which bears the specialised spines is not 

 so great and its margin is much more nearly parallel to the axis of the joint. The 

 spines themselves are rather longer, the lower portion cylindrical and the upper two- 

 thirds tapering to a blunt point. On the posterior side of the shaft about its middle 

 there is a series of small teeth, graduating in size from below upwards, i.e., from large 

 to small. On the opposite side of the shaft, where the tapering begins, there are one 

 or two minute teeth. 



The third appendage closely resembles the previous one, the basis and ischium are 

 subequal in length, the latter being more expanded, the remainder of the limb is 

 similar but on a smaller scale, and the specialised spines are more uniformly digitiform 

 with fewer accessory teeth. In the last appendage (fig. Ig) the ischium is very little 

 shorter than the basis and is dilated dorsally, the merus is about half its length and 

 attains its greatest diameter distally. The propodus is approximately cylindrical, and 

 the few spines that it carries only show the minimum of specialisation. 



The metasome in its entirety is a little shorter than the two posterior segments 

 of the mesosome. 



