THE FEATHER-STAR. 55 3 



years. It is totally unlike the form which it attains when mature, and the relationship between 

 the adult Star-fish and the Pluteus, as the larva is termed, has been well compared to the 

 relation of an embroidery frame to the pictured canvas within. 



The wonderful creature which is called by the name of Shetland Argus is one of a most 

 remarkable genus of Star-fishes, which are remarkable for the vast development of their arms. 



Although the whole mass of arms is of so complicated a description, it will be found, on 

 carefully examining the creature, to be formed by the simple process of twofold division. 

 From the central disc spring five stout arms, each of which almost immediately divides into 

 two smaller arms, and these again into two others; so that in a fine specimen the number of 

 little arms or tendrils, if we may so call them, exceeds eighty thousand. All these organs are 

 extremely flexible, and quite under the control of the animal, winch is able to close or expand 

 them at will. When the extremities of the arms are drawn together, it will be seen that the 

 whole animal assumes the shape of a globular basket ; and in consequence of this resemblance, 

 the name of Basket-urchin, or Sea-basket, has been proposed for the creature. 



It takes its food by means of these wonderful arms, using itself, in fact, like a living 

 casting net, surrounding the prey with the spread arms, and inclosing it within their multi- 

 tudinous lines. It has been known to embrace in this manner a fisherman's bait, and to allow 

 itself to be drawn to the surface without losing its hold. It is one of the deep-sea Star-fishes, 

 and is very seldom taken except by means of the dredge or line. 



The structure of the Shetland Argus is most marvellously complicated, inasmuch as each 

 of the numerous arms is composed of an enormous number of small joints, each exactly in its 

 place, and so beautifully connected together, that they are as flexible as silken cords, and yet 

 as perfectly under the command of their owner as if they were restricted to the original five 

 from which they take their origin. 



The elegant and graceful Star-fish which is appropriately named the Feather-star, is a 

 native of the English coasts, and lias always attracted the attention of sea-side observers. It 

 is not very readily seen, being one of the deep water species, but it may be captured by means 

 of the dredge, and will live for some time in the marine aquarium. It is a very active being, 

 combining in its own person the accomplishments of many different Star-fishes. For example, 

 it can crawl with tolerable speed over the ground, can swim through the water with sufficient 

 power to direct its course, can float about 'at will, driven by the tide, and will sometimes clasp 

 pieces of floating wood, so as to be carried along by the waves without any fatigue. 



Its habits while in the aquarium are very interesting, and have been well described by 

 Mr. Grosse : — 



" In captivity, the Feather-star sits upon the frond of a sea-weed or on a projecting angle of 

 rock, which it grasps very firmly with its clawed filaments, so firmly that it is difficult to tear 

 it from its hold. When violence is used, it catches hold of its support, or any other object 

 within reach, with the tips of its arms, which it hooks down for the purpose, and with its 

 pinnse, so that it seems furnished with so many claws, the hard, stony nature of which is 

 revealed by the creaking, scratching noise they make as they are forced from any hold, as if 

 they were made of glass. 



"I was surprised to observe that several of the arms were unsymmetrically short ; and on 

 examining these with a lens, saw distinctly that each had been broken off, and was renewed ; 

 the new part agreeing in structure and color with the rest, but the joints were much less in 

 diameter ; and this difference was strongly marked at the point of union, the first of the new- 

 joints being not more than one-third as wide as its predecessor. The appearance mttch reminded 

 me of a lizard renewing its tail. 



"In sitting, the Feather-star bends its arms with a sigmoid curve, the tips bending 

 upwards. It waves them now and then, but not much, and remains long without moving from 

 its hold. Though I repeatedly took it out of the water, removing it forcibly, it manifested no 

 tendency to voluntary dislocation." 



Perhaps, however, the strangest part of the Coma tula's life is its early youth. 



Vol. m.— 70. — . 



