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6. Notes on Some North Pacific Holothurians. 



By Hubert Lyman Clark, Professor of Biology, Olivet College, Michigan, U. S. A. 



eìngeg. 15. Mai 1902. 



Through the kindness of Professor D'Arcy W. Thompson, a small 

 collection of Holothurians, made by himself at several points in the 

 North Pacific, was recently placed in my hands for examination. Al- 

 though containing no new species, it extends the range of several species 

 very considerably, and adds quite a little to our knowledge of the dis- 

 tribution of the holothurians of the Pacific Coast of North America. 



1. Chiridota discolor Eschscholtz. 



One specimen from Station 3634 (Albatross), small and contracted: 

 two fragments from Copper Island. These specimens are referred to 

 this species only after comparison with several hundred specimens of 

 North Pacific Chiridotas in the collection of the United States National 

 Museum. The difierences between this and the following species are 

 exceedingly difficult to define clearly, but the color is an important 

 factor, as well as size, texture, etc. 



2. Chiridota laevis (Fabricius). 



One small specimen from Sitka, very similar to specimens from 

 the North Atlantic, except that the color is a little darker. 



3. Cucumaria japonica Semper. 



Four much contracted specimens from Sitka, from 3 to 5 inches 

 in length, and light gray or yellowish-gray in color. These specimens 

 agree well with Lamport's notes on specimens from the Gulf of Geor- 

 gia, and the species seems to be well-characterized by the greatly 

 reduced calcareous ring, the very long Polian vessel and the numerous 

 short stone-canals. The large plates at the opening of the cloaca are 

 not at all noticeable in these Alaskan specimens. The head is drawn 

 back very far, into the body, and the whole anterior end appears to 

 be more slender than the posterior part of the body and the feet are 

 larger and arranged in more regular rows. This portion of the animal, 

 and the tentacles, retain a very decided bronze-red color, which I pre- 

 sume is the color of the animal in life. The differences between these 

 specimens and C. frondosa are very obvious, when the animals are 

 side by side. 



