NO. 1989. ASCIDIANS FROM NORTHEASTERN PACIFIC— BITTER. 445 



3271, 25 fathoms (very near station 3266). — 1 specimen, Granite 

 Cove, Port Althorp, June 18, 1880, Dall collection. — 1 specimen 

 Chamisso Harbor, Eschscholtz Bay, Alaska, 5 to 8 fathoms, W. H. 

 Dall, 1880. 



HALOCYNTHIA WASmNGTONIA, new species. 

 Plate 33, figs. 4-6. 



Superficial characters. — Somewhat egg-shaped, the thick end for- 

 ward; attached along whole ventral side, the area of attacliment 

 much flattened and bordered by a distinct but irregular flange, the 

 test here smooth and thin as compared with that of other regions; 

 surface marked by a number of low, rather regular wrinkles gener- 

 ally running lengthwise of the body (pi. 33, fig. 4) . Siphons not promi- 

 jient, the branchial situated well forward, the atrial more prominent 

 than the brancliial, situated near the median dorsal hne and about 

 midway between the two ends; brancliial orilEice four-lobed, atrial 

 obscurely six- or seven-lobed. Color dark brown, except area of at- 

 tachment, wliich is dull gray. Test stiff and dense, scarcely thicker 

 than heavy paper generally, still thinner over area of attachment. 

 Length 2 cm., width 1.5 cm. Mantle rather thin, even for tliis genus, 

 radial muscle fibers around and adjacent to the siphons as usual 

 much the stronger, the circidar fibers being very fine, especially on 

 the ventral half of the body. 



Respiratory system. — Tentacles 26 large ones, and about as many 

 more very small ones, a few of the large being still larger than the 

 others, the larger copiously branched; brancliial membrane with six 

 folds on each side, from 10-18 longitudinal vessels on the folds and 

 generally 2 between the folds. Stigmata straight, long, and regular, 

 about 6 in a mesh; dorsal languets of reddish color, those at posterior 

 end of series somewhat longer. Hypophysis mouth simple, horseshoe- 

 shaped, the opening directed forward. 



Alimentary system.— On the left side, the rather wide loop occu- 

 pying a nearly vertical position well toward the posterior end; 

 stomach hardly distinguishable from the intestine in size; the lobu- 

 lated gland (hver?) in two widely separated sections, one much 

 more voluminous and elaborately branched than the other (pi. 33, 

 fig. 6). 



Reproductive system. — On both sides, left wholly within intestinal 

 loop; about 35 hermaphroditic lobes on right and 30 on left, lobes 

 on each side not crowded together, all connected to a common strand 

 probably containing both oviduct and vas deferens. 



The most unique feature about this species is the lobing of the 

 atrial orifice. Exactly how many lobes are present in the one speci- 

 men at hand is not certain, but there are clearly five and these do not 

 make up the complete circuit (fig. 5). I Imow of no other species of 

 the genus to wliich more than four lobes of either orifice have been 



