in the centre, so as to close eflectually the lower portion of the 



four subequal portions by botli a longitudinal and transverse artic- 



is composed of a small peduncle supporting a sub-triangulate, di- 

 lated segment, the anterior edge of which is fringed with cilia, and 



edge : when these two lips meet in the centre the parts are osse- 

 ous and triangular; the apex is armed with a small rigid tooth. The 

 first pair of feet corresponding to the second foot-jaws, are attached 

 to the head a short distance from the lower lip, laterally ; they are 

 directed forward and laid on the mouth in such a manner as if con- 

 stituting one of the organs of manducation, six-jointed ; the sec- 

 ond, third and fourth nearly equal, short and irregular, seeming 

 to form a kind of wrist for supporting a rather large, subovoid, di- 

 lated hand, with a termiu;il iucurvcd finger reflected on its inner 

 cihate edge. Abdomen with five transverse articulations, some- 

 what arcuated backwards, their posterior margin is slightly elevat- 

 ed so as to suffer the anterior edge of the following ones to pass 

 under them ; the three first segments have their lateral portions di- 

 vided at the sulcus by a deeply impressed line, or suture, which 

 may be disunited by macerating the parts in water, otherwise they 

 are immovable ; the remaining two are entire : the lateral parts are 

 lalcate and separated from each other by an incisure extendin<r to 

 the longitudinal sulcus, near which, both on their anterior and pos- 

 tenor edges, is situated a small tooth-like process ; a narrow ele- 

 3 along the anterior margin until it becomes obso- 

 ated edge. The second pair of 

 ire attached to the first 

 assist in the process of 

 inyof the other feet, the 

 first joint IS longest, the penultimate one shghtly dilated, formiog 

 a hand with an incurved moveable finger. The four remaining 

 segments are each furnished with a pair of six articulated coriace- 

 ous feet, resembling each other both in size and appearance, being 

 largest at the base, and gradually attenuated to the slightly curved 

 terminal nail ; the first segment is much compressed, the succeed- 

 ing ones tubular and armed at the apex, both forward and behind, 

 wah a number of small moveable spines ; on their anterior edge 



