314 PROCEEDINGS OF THE ACADEMY OF [1888. 



Calcareous bodies, in the form of stools (PI. 15, fig. 3), very 

 numerous. C-shaped bodies scarce, in the form of broadly-opened 

 calipers. Ground-color reddish-yellow, irregularly blotched with 

 black or very dark brown. The spots on the ventral surface more 

 or less coalescent in the median line, forming there a broad longitud- 

 inal band, or entirely united to form a uniformly dark-colored 

 base ; on the back, united into two irregularly ramifying or wander- 

 ing bands. 



Length of longest specimen about ten inches ; width about two 

 and a-half or three inches. 



The same habitat as that of the preceding species, although appa- 

 rently much less abundant. 



I strongly suspect that this is the form which Theel, in his report 

 on the Challenger holothurians (loc. clL, p. 159), identifies with 

 Siichopus Mohii (Semper), one specimen of which, " rather deformed 

 and compressed " when examined by Theel, was obtained at the 

 Bermudas. I assume the identity in this case, as well as in that of 

 the preceding species, on the ground that the two species here de- 

 scribed are the characteristic forms of the archipelago, and it is 

 barely possible that they could have escaped the attention of the 

 Challenger people. But the identification with Semper's species 

 appears to me to be erroneous. The resemblance to Stichopns Mobil 

 appears to rest almost wholly upon the form of the spicules, which 

 are largely similar in many very distinct forms of Siichopus, and in 

 a general scheme of coloring. But Semper distinctly states (Holo- 

 thurien, loc. ciL, p. 246) that the characteristic spots are almost wholly 

 wanting on the ventral surface, and no mention is made of their 

 occurrence there by Lampert, in his revision of the species of the 

 genus (op. cif., p. 108.) Moreover, Semper affirms that the body is 

 devoid of wart-like tubercles, whereas such are quite prominent in the 

 Bermudian form, although not as prominent as in Siichopus diaholi. 

 Theel, however, makes no mention of the occurrence of tubercles in 

 his single specimen, but probably through contraction in alcohol 

 their existence had been effaced. The number of pedicels in each 

 transverse row seiems also to be much more numerous in the Ber- 

 nnidian species than iu Siichopus Mobii. 



Another apparently related form is Siichopus errans of Ludwig 

 (Arbeiieu zoolog. zooiom. Insi., Wurzburg, 1875, p. 97), described 

 from a specimen in the Hamburg Museum, reputed to have come from 

 the Barbados. But in this species there appear likewise to be no 



