454 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.45. 



HALOCYNTHIA VELLOSA (Stimpson). 



Cynthia villosa Stimpson, 1864, p. 160. — Herdman, 1898, p. 258, pi. 12, figs. 



7-11. 

 Pyura villosa Hartmeyer, 1909a, p. 1342. 

 Boltenia villosa Huntsman, 1911, p. 134. 



The only point in which the specunens at hand appear to differ 

 from H. villosa, as redescribed by Herdman in 1898, is in the length 

 of the peduncle. The individual figured by this author can scarcely 

 be called pedunculate at all. In fact, Herdman speaks of the species 

 as being "narrower at the posterior end and sometimes attached by 

 a short stalk." Stimpson, however, states in the original description 

 that the test at the point of attaclunent "is produced into a peduncle 

 which is sometimes as long as the body is thick." In none of the 

 specimens under observation is the peduncle shorter than the body 

 is thick, and in most of them it is considerably longer. Judging, 

 however, by other well-known pedunculated species, we would expect 

 the structure to be subject to much individual variation in length, 

 and hence would not, according to prevaihng notions as to specific 

 differences, regard the differences noted as of specific importance. 



It is worth while to note that considerable variation occurs among 

 the individuals in the number of branchial folds. One specimen had 

 7 folds on each side at the anterior end, and only 6 at the posterior 

 end on the left side. A second specimen had 8 folds on the left, and 

 9 on the right, the ninth being small, while a thh-d had 8 folds on each 

 side. 



The formula for the internal longitudinal vessels of a specimen from 

 Loring, Alaska, was: 



-p, , , [2-5-2-13-2-17-2,-20-2-20-1-15-1-22-0 L. 

 J^ndostyle \^_-iQ_^_^_^_-^g_^_2 1-2-1 8-1-12-1-1 8-1 R. 



A specimen from Puget Sound had the following: 



F H t 1 {'^-'^-^-10-3-15-3-17-4-16-3-20-2-15-1-21 L. 



J^nclostyle ^^_j^__2-10-3-i 1-3-15-4-13-7-19-5-1 1-6-1 l-Q-9 R. 



The Loring specimens are very uniform in external appearance 

 and the echination is decidedly closer and longer than that of the 

 specimens of H. castaneiformis with which I am familiar; Loring, 

 Alaska, 3 to 4 fathoms, Alaska Salmon Investigations, April 30, 1903, 

 26 specimens. 



Puget Sound, on rocks between tides, O. B. Johnson, July, 1889. 

 The 22 specimens m the Puget Sound lot are somewhat less uniform 

 among themselves in external form than the Loring ones. Some of 

 them are almost without the peduncle, as was the one figured by 

 Herdman, while in others the peduncle is quite as' long as in the 



