64 ECHINODERMATA. 



these, however, we may collect, that the early external organs are very 

 few, which is confirmed by the slow and gi-adual evolntion of regenerated 

 parts, to replace the loss of adults in a more perfect state. 



A vigorous young Holothuria is represented two months after its 

 capture, Plate XI. fig. 1. It lost the arborescent apparatus, and died 

 after ha\dng l^een the subject of observation during six months. Eight 

 years previously, a minute milk-white specimen occurred, about four 

 lines long, by one in thickness, the tentacula extending a line at the 

 utmost, distinctly visible by the naked eye, — the whole resembling a 

 maggot, Plate XI. figs. 10, 17. Of the species of that pai'ticular speci- 

 men, however, I speak with some diffidence, owing to the difficulty of 

 getting a satisfactory view. At the same time, its genus was evident. 

 The curvature of the body, the display of the tentacula at night, their 

 introduction into the mouth, where stripped and whence withdra^vTi, 

 besides the firm adhesion, were all the same as in adults. 



Another specimen, little if any larger, with ten tentacula as long as 

 the body, exhibited the same evolutions as those of adults ; absorbing a 

 tentaculum in the mouth, along with one of the antennulae, as above 

 described. Of the identity of this specimen with the fusm I enter- 

 tained no doubt. 



One still smaller than any of the preceeding, of such irregular shape 

 that I incline to think it of another species, survived some months, in 

 1831 . It never extended above an eighth of an inch, having few suckers, 

 some of them unnaturally large ; the whole body perfectly white. This 

 also was maccessible. 



In general these smaller specimens are much bolder than the adults ; 

 but their early nature is consj^icuously shewm by similar habits. The}" 

 endure greater intensity of light, and remain displayed while their ves- 

 sels are moved. The arborescence of all is pale or colourless, while that 

 of adults is grey or crimson, which seems entirely dependent on age. 



The present, and indeed all the Scotish Holothuria?, are free of any 

 oflFensive odour, such as ascribed to the race by some authors, probably 

 from inspecting or dissecting decaying specimens.* 



* Busc, Histoire Naturelle Des Vers, t. ii. pp. 147-151. Paris, 1827. 



