HOLOTHURIA. 29 



like, but I have never found any solid substance whatever in the intes- 

 tines, either animal or vegetable : Nor has any specimen ever testified 

 the least disposition to feed in my possession. 



A very large specimen of the pentades was obtained aljout a year 

 ago, distended by sea-water, so as to be ten inches in length, and six in 

 thickness, the tentacula being contracted to three-fourths of their 

 diameter. Next day it had emptied itself ; it lay motionless, extending 

 16 or 17 inches. The intestines occupied the whole cavity of the body, 

 but they contained nothing except a dark thick fluid matter. 



The natural form and position of the Holothuria pentades is a 

 crescent, so that while quiescent it does in fact bear considerable re- 

 semblance to a cucumber, — whence its name. The body remains affixed 

 by the suckers to the side of a vessel, the head or the portion compre- 

 hending its tentacula remaining free for their evolutions, and the poste- 

 rior extremity likewise disengaged for the play of the fountain. 



In general habits the Holothuria pentades resembles the following 

 subject, but here, the tentacula being formed by a prolongation and 

 adaptation of the integument of the shoulder, they are not immediately 

 connected with the intestines Uke the tentacula of the Holothuria fusus. 

 All the former, that is those of the pentades, being a continuation of the 

 cyhndrical neck, are protruded with its unfolding skin as it extends after 

 having been withdrawn into the body when closed up. — Plate II., fig. 1. 

 The tentacula of i\\e fusus are immediately connected with the intestines 

 by a pecuhar receptacle, wherein the whole can be retracted. Herein, 

 any single tentaculum, or the whole, may be retracted when the ap- 

 paratus constituting the receptacle sinks within the body which closes 

 over it. 



Night appears the chief season of the enjoyment and activity of 

 these creatures. Wliatever be their contracted state through the day, 

 they then expand themselves, and display their beautiful arborescent 

 tentacula at the utmost dimensions. Nevertheless many remain ex- 

 panded through the day, and, whether or not it be from the momentary 

 stimulus, some seem to become more erect on the approach of light, — 

 which is certainly an exception to the general rule, for both hght and 



