168 THE APODOUS HOLOTHURIANS 



MOLPADIA BLAKEI. 



Trochostoma blakei Theel, 1886&, p. Ifi. Calcareous table, fag. 8. 



LENGTH. 60-75 mm., of which about one-tenth is tail. 



COLOB. Whitish, grayish, or very pale brownish. 



DISTRIBUTION. Eeported from near Grenada, 1,720. m. (Theel) ; coast of 

 Senegal, 3,655 m. (R. Perrier), and Gulf of Mexico, 2,126 m. (Clark). 



REMARKS. This is a remarkably well-characterized species, but as Theel 

 neglects to give any dimensions for the curious little tables, it has been easy to 

 mistake some specimens of parva for blakei. Several specimens of parva were 

 labeled blakei by me, and I then decided the two were synonymous, and it was 

 only when I found a specimen of the true blakei that I realized my mistake. 

 Perrier 's ( :03) specimen was very small, but the tables are characteristic, at 

 least as far as the dimensions go. The differences he points out between his 

 specimen and Theel 's are interesting and may possibly prove to be specific. 



MOLPADIA ANTARCTICA. 

 Trochostoma antarcticum Theel, 1886a, p. 44. Calcareous particles, pi. 11, fig. 7. 



LENGTH. Up to 92 mm., the tail only 3-5, and the diameter 20-25. 



COLOR. Gray, colored or blotched with yellowish brown, especially ante- 

 riorly and dorsally. 



DISTRIBUTION. Reported from southern coast of Chile (Theel, Clark) ; Gulf 

 of Mexico (Theel), and off Alexander Land, Antarctic Ocean (Herouard). 



REMARKS.- Theel has expressed some doubt as to the validity of this 

 species, but it is clear from the material in the United States National Museum 

 that the southern form is quite distinct from either arctica or borealis. As for 

 the three specimens from the Gulf of Mexico, which Theel ('86&) assigns to ant- 

 arctica, I am strongly inclined to believe they represent quite a distinct, and 

 probably undescribed, species. The species arctica and antarctica are nearly 

 allied and young specimens might easily be confused, but specimens over 50 

 mm. are readily distinguished. The skin in antarctica is very thin and delicate, 

 and even specimens 14 mm. long have no anchors or rosettes, so the species ap- 

 parently has no ankyroderma stage. The single specimen which Herouard 

 ( :01) had, seems to have been of this species, although he implies that the ab- 

 sence of calcareous deposits was due to decalcification. Regarding Lampert's 

 ( '89) record of this species from New Guinea, see under andamanensis. 



MOLPADIA PARVA. 



Trochostoma arcticum Marenzeller, var. parva Theel, 18866, p. 17. 

 Trochostoma arcticum Marenzeller, var. cceruleum Theel, 1886&, p. 17. 



LENGTH. 60-80 mm., of which about one-tenth is tail. 



