NO. 19S9. A8C1DIAN8 FROM NORTHEASTERN PACIFIC— RITTER. 439 



Albatross stations: 3238 (1 specimen), lat. 58° 3' 40" N.; long. 158° 

 37' 30" W., IS fathoms, fne. gj. s., June 7, 1890 (Bering Sea); 3292 

 (3 specimens), lat. 57° 14' N. ; long. 159° 35' W., 32 fathoms, bk. s. g., 

 July 18, 1890 (Bering Sea); 3293 (1 specimen), lat. 57° 30' N.; long. 

 159° 33' W., 30 fathoms, fne. gy. s., July 18, 1890 (Bering Sea); 

 3296 (2 specimens), lat. 57° 26' 30" N.; long. 158° 46' W., 24 fathoms, 

 gy. s. bk. sp., July 19, 1890 (Bering Sea); and 3303 (1 specimen), lat. 

 57° 27' N.; long. 160° 23' 30" W., 33 fathoms, bk. s., July 21, 1890 

 (Bering Sea). 



All these stations are in the southeastern part of Bering Sea. 



Other stations: Nikolski, Bering Island (2 specimens), Albatross 

 Jime 3, 1892; No. 2502, Commander Islands, Siberia (2 specimens), 

 Leonhard Stejneger, collector, 1882-83. 



Many of the specimens were associated with Boltenia ovifera. 



MOLGULA CRYSTALLINA (MoUer). 



Clavelina crystallina Moller, 1842, p. 95. — Hartmeyer, 1903, p. 134. 



Peru crystallina Verrill, 1872, p. 290, pi. 8, fig. 9.— Hartmeyer, 1899, p. 455, 



text fig. A; pi. 22, fig. 1; pi. 23, figs. 1, 16. 

 Caesira crystallina Hartmeyer, 1909a, p. 1323. — Van Name, 1912, p. 494, text 



figs. 12 and 13; pi. 48, figs. 31-33. 



The MolguUds grouped together under this name have but five folds 

 in the branchial sac, and for this reason have, with several other 

 species possessing the same peculiarity, been made into a distinct 

 genus, Pera. It is with some hesitation that I refuse to recognize 

 this generic group. On the whole it seems to me advantageous to set 

 off from so large a genus as Molgula, any smaller group when this 

 can be done on the basis of so distinctive a character as that here 

 mentioned. However, so long as Molgula as usually accepted, 

 contains one lot of species having six folds, and another lot having 

 seven, I conclude that on the whole, for consistency's sake, the 

 species with five folds should also be retained. 



Some of the specimens examined appear to be without the peduncle, 

 as Hartmeyer, 1899, states is the case with some of the specimens in 

 the collections studied h^ him. Hartmeyer found that whereas the 

 species had been described as having about 12 tentacles, close study 

 revealed to him 144, in 5 sizes, many of them being very small. 

 My observation too, is to the effect that all but 20 or so of the largest 

 are likely to be overlooked. 



Localities. — Although the species was not taken in quantity any- 

 where, a few specimens are at hand from eleven stations. These are : 



Albatross 3213, latitude 54° N.; longitude 162° 54' W. (a little south 

 of the Alaska Peninsula), 41 fathoms, bottom bk. s.. May 21, 1890; 

 two small specimens. 



Albatross 3214, 54° 13' N.; 163° 06' W., 38 fathoms, gy. s. g.. May 

 21, 1890; 1 small specimen. 



