HOLOTHURIA. 51 



the faintest red. Fifteen weeks having elapsed from the date of mutila- 

 tion, the regenerated portion had not only recovered its most important 

 organs, but all these were discharging the wonted natural functions, 

 sweeping the water, then curving into the mouth, which dilated for their 

 reception, and contracting as they withdrew. 



Thus did increment gradually advance. The ramifications, aug- 

 menting both in size and number, were stained with lake coloured 

 patches, especially at the angles, and on the thirteenth of June, when, 

 having attained nearly their ultimate dimensions, the funnel which they 

 formed occupied a circle of about five inches in diameter, Plate IX. 



In this manner was the whole of such a singular, beautiful, and 

 compUcated fixbric reproduced from its very origin, while a fortunate 

 concurrence of circumstances permitted uninterrupted observation of its 

 progress. 



Though the parts exposed externally were so conspicuous, and so 

 interesting, they enlarged stiU farther ; but I cannot affirm that they 

 ever attained the dimensions of a full grown specimen, or the colour 

 proper to the subject or the species. The arborescence was neither so 

 luxuriant nor so dark. After eighteen months' increment the hue was 

 only deepenmg. That of the largest specimens probably tends either to 

 red, or to some combination wherein red is jiredominant. 



Perhaps in its native state, in its orginal abode, and with ample 

 congenial sustenance, reproduction might have advanced quicker, and 

 with deeper colours. On the other hand, the higher temperature of 

 an apartment than of the sea ought to promote more speedy organic 

 evolution. Let it be remembered also, that nascent organization is always 

 paler, and that the elements of the animal creation are hidden in trans- 

 parency. Whatever be the colour peculiar to the embryonic stages, the 

 young Holothuria is perfectly white some time after exclusion from the 



egg- 



The specimen Plate XI., fig. 1, was of the palest grey, the tentacula 

 quite transparent, and as long as the body. The same is seen of others, 

 — one much smaller, for example, which, when they were retracted, 

 might be compared to a large grain of com. The tentacula of each were 



