ASTEROIDEA OF NORTH PACIFIC AND ADJACENT WATERS — FISHER 



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marginals are marked by the pebbling so characteristic of Eustolasterias and certain 

 allies. The integument of Sclerasterias guernei is not thicker than that of young 

 S. heteropaes in the definitive phase. The transverse dermal furrows between con- 

 secutive skeletal arcs of Sclerasterias, darker in color and passing from the adambu- 

 lacrals of one side across the ray to the other, are equally characteristic of "Eustol- 

 asterias." In large specimens these fine furrows become more numerous and irregu- 

 lar and doubtless are lined with special nerves and cilia. The specimen of Scle- 

 rasterias guernei, from the Bay of Biscay, identified by Dr. R. Koehler and now in the 

 British Museum, has a slight inferomarginal web, which is discernible also in the 

 paratype from station 60 (Bay of Biscay, 300 meters). Finally, the crossed pedi- 

 cellariae of S. guernei are similar to those characteristic of Eustolasterias. The small 

 enlarged tooth on the outer side of the terminal dentiferous lip is very similar to that 

 of other related species, as figured on Plate 52. 



The specimens of S. guernei are small, R 17 mm. or less, that figured by Perrier 

 being the smallest. Koehler states that they may reach a size with R 34 mm. The 

 diminutive size of the specimen figured by Perrier would seem to indicate the absence 

 of a fissiparous six-rayed stage such as is characteristic of S. euplecta, S. alexandri 

 and S. lieteropaes. Yet little is known of S. guernei beyond the fact that it lives in 

 the Bay of Biscay region, in from 190 to 500 meters. Whatever may be its early 

 history, I am unable to find tangible characters by which to separate it from the 

 group later named Eustolasterias by me. The apparent differences mentioned in my 

 synopsis (1923) are fictitious, and were derived from Perrier's description and figures. 



Component species. — The genus Sclerasterias comprises the following species: 



i A specimen of Asterias linearis Perrier (No. 1270, Mus. Comp. Zool., Barbados) with R 26 mm. appears to be young 

 contorts. 



' Asterias peregrina Bell. I have seen the type so labeled in the British Museum but the description was apparently 

 never published. 



' Eustolasterias sUnactit n. L. Clark, Union of South Africa. Fisheries and Marino Biological Survey, Report No. i. 

 Special report 7, pt. 2, May, 1926, p. 23, pi. 4. This probably Includes the "percarina" above. 



The species which I have personally examined are marked by an asterisk. 



Three forms, euplecta, hypacantha, and stenactis, are closely related and appear 

 to be small species or races of a wide-ranging species. Probably mazophora is in the 

 same category. After more experience with this genus I am inclined to give much 



