246 



Among the specimens brought by Mr. Stimpson from South 

 Carolina are several of Colochirus gemmatus Pourt. obtained at 

 Fort Johnson in shoal water. In accordance with the plan ori- 

 ginally proposed in my notes on this family, the following de- 

 scription is annexed, specifying some points not mentioned by 

 Count Pourtales. 



The body is fusiform, with both extremities elevated, about 

 five inches in length with a breadth of one inch, tapering more 

 posteriorly than anteriorly. The surface is densely covered 

 with minute, irregular, calcareous laminse, each pierced with 

 four or five holes. These, by their abundance, render the walls 

 of the body so rigid as perhaps to prevent much change of form 

 in the animal. 



H\\Q suckers are numerous. Their sides are covered as thickly 

 as the adjacent surface ; the plates are much elongated, some- 

 times bent, widest in the middle, perforated. The terminal^ 

 transverse plate is quite small. The neck, about half an inch 

 in length, is destitute of suckers. 



The tentacula are ten, the two on the ventral side very small. 

 The remaining eight are ramose, rather short, having their 

 trunks and principal branches rigid with calcareous deposits. 

 The laminse are less elongated than those of the suckers, pierce'd 

 with very numerous foramina. 



The oral circle consists of ten pieces. Five are short, rounded 

 posteriorly, and bifid anteriorly. The alternating five, to which 

 the retractor muscles are attached, project further forward, and 

 are also prolonged posteriorly each into two slender branches. 

 Thus the entire circle presents the appearance of five short 

 points forward (each slightly bifid,) and ten long ones backward. 



The intestinal canal is of nearly uniform diameter, a little 

 more than three times the entire length of the animal. 



The genital tubes, undivided, are attached in a cluster to the 

 intestine, at a point rather more than half the length of the body 

 backward. The duct passes forward as usual. 



The pyriform sac is slender, about three fourths of an inch 

 long. 



The respiratory trees are two, about equalling the body in 

 length. 



In color the animal appears to have been of a dark brown. 



