linl.ul liritlA. 73 



It w of more irregular shape than tin- preceding species; rather 

 cylindrical on tin- whole, the largest extending two inches by about 

 three line*, or scarcely as much, in thickness. Numerous extensile 

 peduncles or suckers are scattered over the body without definite arrange- 

 inrnt, though sometimes up|Mirentl\ in five or six irregular rows. All 

 are of uniform colour, pun-, or ding)- white, and yellowish-brown. 

 Plate XIV., fig. 1. 



Tin- anterior extremity, closed during quiescence, opens for the pro- 

 trusion of an arborescent apparatus, consisting of eight tentacula, and 

 two antennukv, thus corresponding \s ith the same number of these organs 

 in tin- Iliilnllniria fiuiu, Plate XIV.. fig. 2. The office of the organs 

 themselves also seems to be of the same nature, figs. 3, 4, 5. But neither 

 tentacula nor antennulo) are equally luxuriant as those of that species ; 

 and the teutaculum, consisting of a stout stem, with branches propor- 

 tionally shortening upwards, set alternately, having few subdivisions or 

 subordinate parts, is inferior to that of the pentodes likewise, figs. C, 7, 8. 



The tentacula of some extend towards six lines, the antennuUv 

 about half as much, fig. 9, enlarged ; tentacula and antennuke. The 

 stem of the tentaculum is peculiarly organized, being distinguished by 

 minute prominences disposed in spiral lines. 



Little discrepancy prevails in this animal's habit*, and those of the 

 Holothuriae previously described. It sometimes remains long quiescent, 

 and at others is very active, traversing its vessel freely with the ten- 

 tacula displayed in front. While quiescent the whole arborescent appa- 

 ratus is retracted within the body. As this apparatus is formed by a 

 prolongation of the skin, ite structure is different from that of the cor- 

 responding parts of the/M*/ and pentactes. 



Moderate temperature, together with frequent renovation of their 

 element, seems congenial to every species of the whole tribe. During 

 fine weather the tentacula are readily displayed, and often remain so 

 during much of the day. Some keep them always expanded, allowing 

 their vessel to be exposed to the light without contracting or retreating. 



They rise to the surface to escape the impurity of the wat. 



The prevailing colour is perhaps affected by their site ; I remarked 



