184 THE APODOUS HOLOTHURIANS 



Color. — Gray mottled with numerous small patches of red-browii. 



Distribution. — Reported only from "Albatross" Station 3603, near the 

 Aleutian Islands, 3,188 m. (Clark). 



Remarks. — This is one of the "Albatross' " most interesting discoveries in 

 the way of holothurians and adds another to the long list of remarkable ani- 

 mals acquaintance with which science owes to that vessel. The three specimens 

 taken occurred on a bottom of "blue ooze." 



HIMASTHLEPHORA Clark (antca. p. 40). 



Tentacles 15, with four digits of which the terminal pair are the largest; 

 without ampulLT. Body nearly cylindrical, rather stout, terminating abruptly 

 in a long, slender caudal portion. Mid-dorsal interambulacrum with 4-6 whip- 

 lash-like papillae. Rudimentary pedicel-like outgrowths near both the anterior 

 and posteiior ends of the body. Genital papilla prominent, 2 mm. or more in 

 length. Respiratory trees small and delicate. Longitudinal muscles simple, 

 flattened and unpaired. Calcareous ring of 10 pieces, rather stout and synapta- 

 like with no posterior prolongations. No calcareous or phosjihatic deposits in 

 skin. Careful examination of two specimens failed to show a stone-canal. 



The specimens on which this ^euus is based were collected in 1886 and ex- 

 amined by me in 1900. In 1905 appeared the description of the following 

 genus, and it occurred to me at once that the "Investigator's" novelty is very 

 closely allied to this one discovered by the "Albatross," if not actually con- 

 generic with it. The most obvious ditfereuce between the two is in the shape 

 of the body — that is, the presence or absence of a caudal apjjendage. I con- 

 sidered it present very plainly in the four "Albatross" specimens, while 

 Koehler and Vaney consider it wanting in the two "Investigator" specimens. 

 I am now unable from the available material to satisfy myself beyond doubt on 

 this point. An apparent caudal appendage was present in all four specimens, 

 but the condition of the material was such that even the stained sections pre- 

 pared would not permit me to determine whether the appendage was a normal 

 outgrowth. covered with skin or an evagination of part of the alimentary canal, 

 which is unfortunately ruptured and macerated beyond satisfactory examina- 

 tion. The position of the clusters of pedicel-like outgrowths at the base of the 

 api^endage is suspicious, and a study of the description and figures given by 

 Koehler and Vaney increases the suspicion that the apparent tail is not a 

 normal outgrowth. On the other hand, its presence in all four specimens and 

 its general appearance argue in favor of its being a caudal appendage, es- 

 pecially since the respiratory trees were in their normal position in the body- 

 cavity. If the appendage were an evagination, it seems as though the respi- 

 ratory trees must have been injured or disturl^ed. Aside from this doubtful 

 appendage, Himasthlephora differs from Gephyrothuria in the number of digits 



