TUNICATA OF THE PRIBILOF ISLANDS. 



513 



0.2 mm. apart; intermediate transverse vessels, i. e., vessels crossing the stigmata, 

 frequently present, but small. About 20 stigmata in the space corresponding to the 

 interval between two internal longitudinal vessels. The series of stigmatae extend 

 fully to the dorsal lamina. (Fig. 3.) 



Dorsal lamina a plane narrow membrane. "Endocarps" (fig. 5 en'c.) present, 

 numerous, and rather large, contain many pigment cells. 



Digestive tract. — Situated on left side of branchial sac, the portion posterior to 

 the stomach forming an S, the two loops of which are closed; the end of the limb of 

 the S corresponding to the pylorus is extended to form the stomach and oesophagus ; 

 the two last-mentioned parts of about equal length. (Esophagus issues from the 

 dorsal side of the branchial sac. Stomach not well set off from intestine; consid- 

 erably longer than broad, its walls with numerous internal folds, but smooth on outer 



surface; rectal portion of intestine runs 

 J ^If close along the oesophagus, but extends 



farther forward than mouth of (BSopha.gus. 

 r Sexual organs. — On the right side of 



J ^, J L.J UlJ 



the animal only, closely attached to the inner surface of the mantle. Ovary (fig. 5,ov.), 

 a long, branched, cylindrical body of uniform diameter throughout, the whole consist- 

 ing of a basal portion situated near to and extending approximately parallel with the 

 midventral line, and five or six simple branches given off from this basal piece, these 

 reaching dorsalward and being inclined somewhat toward the anterior end of the 

 animal. 



This species clearly belongs to the genus Dendrodoa, founded by MacLeay, 1824, 

 as a subgenus of Ascidia. His species was from Winter Island, in Pox Channel. 

 Until now no other member of the genus has been described. 



The chief differences between the present species and D. glandaria, MacLeay, are 

 as follows : 



The test of the latter is described as "whitish, subpellucid, coriaceous, and 

 smooth ;" and in another connection the author speaks of the ovary as being visible 

 5947_PT 3 33 



