254 The British Star-Fishes. 



says, be readily mistaken for the torn- off" skin of some bulkier 

 species. Its surface is covered with slightly elevated tubercles, 

 which bear very closely-set fasciculi of short and sharp spines. 

 It is one of the rarest of our native forms, being altogether an 

 inhabitant of deep water, and is mostly found very much 

 denuded of its spines. 



Asterias aurantiaca and Luidia fragilissima* present a 

 surface structure very different from any of the species pre- 

 viously noticed, their tuberculated epidermis being so closely 

 set with upright spines, as to be almost wholly invisible. 

 These spines are arranged in a radiated or rosette-shaped 

 manner, and have a roughened surface. A portion of the ray 

 of Luidia forms a microscopic object of exquisite beauty: it is 

 represented in Fig. 2 of the tinted plate. The excessive fragility 

 which characterizes many star-fishes is in no instance better 

 shown than in Luidia. Forbes gives the following graphic 

 account of the capture of one of them, probably off the coast of 

 the Isle of Man : — " It is the wonderful power which the 

 Jjuidia possesses, not merely of casting away its arms entire, 

 but of breaking them voluntarily into little pieces with great 

 rapidity, which approximates it to the Ophiurw. This faculty 

 renders the preservation of a perfect specimen a very difficult 

 matter. The first time I ever took one of these creatures, I 

 succeeded in getting it into the boat entire. Never having 

 seen one before, and quite unconscious of its suicidal powers, 

 I spread it out on a rowing bench, the better to admire its 

 form and colours. On attempting to remove it for preservation, 

 to my horror and disappointment I found only an assemblage 

 of rejected members. My conservative endeavours were all 

 neutralized by its destructive exertions, and it is now badly 

 represented in my cabinet by an armless disk and a diskless 

 arm. Next time I went to dredge on the same spot, deter- 

 mined not to be cheated out of a specimen in such a way a 

 second time, I brought with me a bucket of cold fresh water, 

 to which article star-fishes have a great antipathy. As I 

 expected, a Luidia came up in the dredge, a most gorgeous 

 specimen. As it does not generally break up before it is 

 raised above the surface of the sea, cautiously and anxiously I 

 sunk my bucket to a level with the dredge's mouth, and pro- 

 ceeded in the most gentle manner to introduce Luidia to the 

 purer element. Whether the cold air was too much for him, 

 or the sight of the bucket too terrific, I know not, but in a 

 moment he proceeded to dissolve his corporation, and at every 

 mesh of the dredge his fragments were seen escaping. In 



* Luidia fragilissima, Forbes, is now sub-divided into two species, L. Sarsii and 

 L. Savijnii, t lie one having live and the other seven rays. The two species, how- 

 ever, present no structural differences. 



