1908.] NATURAL SCIENCES OF PHILADELPHIA. 331 



Lepidonotus caeloris Moore. 



Lepidonotus cdloris Moore, Proc. Acad. Nat. Sci. Phila., 1903, pp. 412-414, 

 PI. XXIII, fig. 12. 



This species, originally described from specimens dredged off the 

 coast of Japan, proves to be one of the most abundant and generally 

 distributed species of Polychaeta throughout the region covered by these 

 explorations. It represents in the North Pacific the widely spread 

 L. squamatus of the Atlantic, but is quite distinct from that species. 

 The detached submarginal t\ift of cilia that is so conspicuous and 

 constant a feature on the elytra of the latter species is quite absent in 

 the former, in which, also, the marginal flask-shaped sense organs are 

 very much fewer and smaller. The outer surface of the elytra is less 

 hairy and beat's more numerous and rather smoother papillae. ]\Iuch 

 variation is evident in the size, number, arrangement and sculpturing 

 of the papilla? and in the color of the elytra, some specimens being 

 nearly black, others reddish brown, and still others orange or yellow. 

 The neuropodial setse are quite distinct from those of L. squamatus, 

 being more slender, less strongly hooked, more extensively ctenate and 

 in a greater number of rows. 



All of these differences are most apparent in the adults, especially 

 when individuals of equal size are compared. The young of L. cccloris 

 much more closely resemble the Atlantic species, especially in the 

 greater hairiness of the elytra, and it seems not improbable that the 

 small specimens of L. squamatus recorded by Johnson from Puget Soimd 

 and California and by Marenzeller from Japan may be of this species. 

 It is also not improbable that intermediate forms may be found to con- 

 nect the two in the Arctic regions, in which case L. cantoris would 

 become a well-marked subspecies. 



Represented in the collections by a greater number of individuals 

 than any other species, Lepidonotus caloris was found at many points 

 between Vancouver and Kadiak Islands, at depths ranging from 18 to 

 313 fathoms and on most kinds of bottom, though naturally most often 

 on mud. It was most abundant on muddy bottoms in the Gulf of 

 Georgia, on a gravelly bottom with sponges at Station 4228, near 

 Naha Bay in the Behm Canal, and on a bottom of rock and broken 

 shells at Station 4253 in Stephens Passage, Alaska. 



The stations at which Lepidonotus c(eloris was taken are 4192, 4193, 

 4197, 4198, 4227, 4228, 4234, 4235, 4239, 4245, 4253, 4258 and 4274. 



Polynoie tuta Grube. 



Polynoe tuta Grube, Arch. f. Naturges., XXI, 18.55, Bd. I, p. 82. 



Harmothoe tuta Johnson, Proc. Ros. Soc. Nat. Hist., XXIX (1901), pp. 394, 6. 



Of the three examples of this species in the collection, the one from 



