40 ECHINODERMATA. 



angles to the adhering body. Though in itself rigid, this shelly organi- 

 zation is flexible in relation to the other parts, from the pliancy of the 

 lower intestinal portion, from which it originates. 



Each tentaculum is independent of its fellow, and each subordinate 

 member, branch, or twig, is free of all the rest. The funnel is constituted 

 by the common expansion of the whole, and for this the night is chiefly 

 chosen. But so timid is the creature, that amidst the fullest display 

 and the most ample exercise of its arborescent organs, while sweeping 

 through the water in obvious enjoyment of renovated invigoration, the 

 slightest shock, or an approaching taper, though there be no eyes to be- 

 hold it, interrupts the tentacular evolutions ; the cylinder recedes, the 

 branches contract, and the whole apparatus, now resembling a rich 

 cluster of rye grass, is quickly withdrawn. In disappearing from view, 

 the shaggy coat closes over it, without leaving a trace of the opening 

 whence it had issued. 



Then will the animal remain in pertinaceous retreat, not only for 

 the coming night, but for several ensuing. 



It may seem extraordinary that such a large and complex organiza- 

 tion shall be reduced so expeditiously, as to be confined within the 

 cavity of the body undistended by its reception ; or, speaking more cor- 

 rectly, that each tentaculum shall be received in its shelly sheath, not 

 exceeding six or seven lines in length, and scarcely one in diameter. 



But all the arrangements of nature are perfect in themselves. They 

 are so constructed, that neither check nor embarrassment shall impede 

 their application and use. 



We may conclude that the infinite parts of the arborescent tentacu- 

 lum are tubular, that they are distended by a fluid in attaining their full 

 dimensions, which is suddenly discharged to operate their reduction. 



The fact is shewn in the detail of their formation, exposed by the 

 origin or root of the respective members. While displayed, the whole 

 quickly collapsing, are withdrawn : When returning to resume their 

 evolution, absorption replenishing the cavities adapts them for their 

 proper functions. 



It is thus that the great Architect provides for his marvellous works. 



