528 



THE FUR SEALS OF THE PRIBILOF ISLANDS. 



£3^. 



seen with difficulty. Ganglion not spherical, not large. Tentacles not numerous, 

 apparently about twelve, presenting a peculiar distorted, shriveled appearance, situ- 

 ated very close around the base of the siphon. (Fig. 23 A). 

 Branchial sac consisting of about twelve series of long, narrow, 

 regular stigmata. A well-developed muscle band in each in- 

 terserial space. (Fig. 23 B.) Dorsal languets long and slender, 

 one for each series of stigmata. Bndostyle nearly straight, 

 moderate in size. 



Digestive tract. — (Esophagus issuing from the branchial 

 sac at its postero-dorsal angle. Nothing characteristic in the 

 general form and proportions of the tract as a whole. Stomach 

 distinctly longer than broad. Folds of its wall distinct, about 

 six extending the entire length of the organ, and in addition 

 two or three shorter and narrower ones on one side; in some 

 cases these strongly suggesting the areolated condition (fig. 23). 

 Eectum terminating in a broad, trumpet-shaped anus. 



Sexual organs. — Ovary small, situated in the post-abdomen, 

 a short distance behind but not in contact with the intestinal loop. Testis occupying 

 nearly the whole of the remainder of the long post-abdomen. The numerous rather 

 small regular lobes are distinctly visible, those of the anterior 

 narrower portion of the post-abdomen forming a single row only 

 in many specimens. Vas defereus conspicuous, passing to left 

 of intestinal loop. No embryos seen. 



This species has much in common with A. pribilovense when 

 the two are compared with reference to the zooids only; though 

 from this standpoint they are rendered specifically quite distinct 

 by differences in size, in the atrial languets, and in the folds of 

 the stomach wall. The greatest difference between them, how- 

 ever, as will be noticed, is in the general character of the colony. 

 These species would appear to be somewhat closely related to A. J2S/3. 



mutabile, Sars, though, as I know this form only by the figures 



and partial description given by Huitfeldt-Kaas, 1S9C, I am unable to mate a com- 

 plete comparison between them. A. mutabile is, however, represented as having a much 

 more distinctly 3-lobed atrial languet than either of my species, 

 and also with only 4 furrows or folds in the stomach. It is there- 

 ^J- >|jfe\ fore well set off from the present species. There are about 8 col- 



onies of this species in the collection, all from St. George Island. 

 Amaroucium dubium, new species. 



I designate by this name a species of Amaroucium collected 

 by Mr. Leoiihard Stejneger at Copper Island during his visit there 

 in the summer of 1897. There are only three fragments of colonies 

 at hand, and as these are considerably eroded, apparently from 

 having been torn from their anchorage and washed about by the 

 waves, and as the zooids are all in a state of extreme contraction, 

 I have hesitated very much about describing it as a new species. 

 As, however, sufficient information concerning its structure is obtainable to show it 

 to be ditt'erent from any hitherto described species of the genus, I have concluded 



