1869.] 105 [Agassiz. 



ence to this point, but I wish at the same time to be distinctly under- 

 stood as not denying on this account the fact of the existence of 

 these animals at great depths, but simply to show how cautious we 

 should be in making broad generalizations from the presence of a few 

 animals at a,ny one point, the habits of which we know nothing about. 

 Carpenter, in his report on the deep sea dredging of the English 

 Expedition of 1868, mentioned an Astropecten as attached at a dis- 

 tance of two hundred and fifty fathoms from the dredge, twelve hun- 

 dred fathoms being out. Ross, while sounding at a depth of one 

 thousand fathoms, found on the sounding line at a depth of eight 

 hundred fathoms, a species of Euryale, and again while sounding at 

 a depth of one thousand fifty fathoms, below the point marked 

 eight hundred fathoms, a small starfish was found attached to the 

 sounding line. Carpenter and Wallich both saying that "it is 

 irreconcilable with what we know of the habits and structure of the 

 Echinoderms, to suppose that the Caput Medusas (Euryale) and small 

 starfishes referred to could have been found free, floating and alive, 

 at a distance of two hundred fathoms from the bottom." x Carpenter 

 says of the Astropecten, 2 "As this animal is entirely unfurnished with 

 swimming organs, and was found to be of such specific gravity as to 

 sink immediately when placed in ajar of seawater, it can scarcely be 

 taken up anywhere else than from the sea bottom." 



Any one who has ever kept starfishes alive in a tank, cannot fail 

 to have observed the tendency they have to creep up along the sides 

 of the tank till the foremost arms reach the top of the water. They 

 then continue to creep on, the anterior arms, however, not protruding 

 out of the water, but turning over, spread with the suckers uppermost, 

 extended to the fullest extent. This is carried so far that the starfish 

 are frequently attached to the side of the jar or tank, only by a very 

 small portion of the extremity of one arm, where the suckers are 

 least powerful, and a portion by far too small to form a fulcrum for 

 the upholding of the rest of the starfish in that attitude. If we ex- 

 amine the starfish (Asteracanthion herylinus) in that attitude, we shall 

 find also that the body is by no means rigid, on the contrary the 



i Wallich, G. C. The North Atlantic Sea Bed. London, 1862, p. 80. 



2 Carpenter, Dr. W. B. " Preliminary Beport of Dredging Operations in the Seas 

 to the North of the British Islands, carried on in her Majesty's steam vessel 

 Lightning," by Dr. Carpenter and Dr. Wyville Thompson. From Proc. of Royal 

 Soc. No. 107, 1868, p, 171. 



