1908.] NATURAL SCIENCES OF PHILADELPHIA. 323 



SYLLIDiE. 



Syllis armillaris (Mailer) Malmgren. 



Nereis armillaris Mtillor, Zoologise danicse prodromus, 1776, p. 217, 



Syllis armillaris, Malmgren, Annulata Polychaeta, 1867, p. 42, Tab, VII, fig. 



46, 

 Syllis borealis Malmgren, ibid., p. 42, Tab. VI, fig. 42, 

 Typosyllis armillaris, Marenzeller, Ann. K, K. Naturh, Hofmuseums,V(1890), 



p. 3. 



Two small and immature examples 11 imn. long agree well with the 

 descriptions cited above and bear out fully Marenzeller's conclusions 

 concerning the synonymy of the species and confirm his record of its 

 occurrence in Bering Sea, One specimen is beautifully marked with 

 dainty transverse lines of dark brown or black pigment; there being 

 two lines across each segment as far as XV and beyond that point one 

 line to the middle of the body. The accessory tooth at the tip of the 

 setae, which was overlooked by Malmgren, is almost always present. 

 The median tentacle has 15 joints, the paired tentacles 11 to 14 joints, 

 the dorsal and ventral peristomial cirri 15 and 10 respectively^, the first 

 dorsal cirrus (somite II) 18 joints, the middle dorsal cirri 9 to 14 joints, 

 with the greatest diameter at the 4th or 5th, and the caudal cirri 14 

 joints. In one specimen the gizzard extends from somite XIII to 

 XXII. 



Stations 4261, Dundas Bay, Icy Strait, Alaska, July 24, 8^10 

 fathoms, green mud and rocks; 4289, Uyak Bay, Kadiak Island, 

 Alaska, 74-80 fathoms, gray mud, 

 Syllis alternata new species. 



The type and largest example (from Station 4228) is 30 mm, long 

 with 160 segments, the posterior 28 of which are filled with eggsi 

 without, however, exhibiting any sign of stolonization. Other examples 

 are from 16 to 20 mm. long with from 116 to 125 segments. The form 

 is slender and the diameter nearly uniform, the body slightly widened 

 to about XX, strongly arched above and flattened below. The seg- 

 ments are all sharply defined and very short, usually 6 to 8 times as 

 wide as long. 



The prostomium (a) is about H times as wide as long, as shown in 

 the figure of a cotype, but may be partly concealed beneath a fold of 

 the peristomium. Slight anterior and posterior contractions give 

 the effect of prominently bulging sides. The palpi are about twice the 

 length of the prostomium, project prominently straight forward and 

 are narrow distally. Of the two pairs of small reddish-brown eyes, the 

 anterior are larger, decidedly farther apart and crescentic or bean- 

 shaped as seen from above. In the type specimen the two pairs of 

 eyes are closer together but riot larger than in the smaller specimens. 



