POLYCHAETE WORMS, PART 1 139 



4. Stem form with sexual buds formed in chains of 2 to 8 (rarely singly; fig. 40a). 

 Sexual stolons with usually 3 prenatatory setigers (2-4 in female); usually 

 2 pairs tentacular cirri (1 or 2 pairs in female); in female stolon, tentacular 

 cirri similar to the following dorsal cirri (fig. 406) ; in male stolon, upper pair 

 tentacular cirri very long, similar to median antenna (fig. 40c). 



A. prolifer 

 Stem form with sexual buds formed singly (?). Sexual stolons with 14 pre- 

 natatory setigers (sometimes 13?); tentacular cirri 2 pairs; in male stolon, 

 first pair dorsal cirri very long, similar to median antenna . . A. alexandri 



Autolytus cniertoni Verrill, 1881 



Figure 37c 



Autolytus emertoni Verrill, 1881, pi. 12, fig. 9 (figure only). — Sumner, Osburn, and 

 Cole, 1913, p. 616.— Hartman, 1942b, p. 43, fig. 59.— Miner, 1950, p. 296, 

 pi. 97. 



Description. — Stem form unknown. Female stolon with 6 pre- 

 natatory, about 24-26 natatory, 16-43 postnatatory setigers; tentac- 

 ular cirri 2 pairs, without nuchal epaulettes; dorsal cirri very short, 

 especially anterior 6 pairs; egg sac single, elongated. Male stolon 

 with 6 prenatatory, 26-35 natatory, 15-20 postnatatory setigers; 

 tentacular cirri 2 pairs, upper pair long, similar to median antenna, 

 lower pair shorter. 



Biology. — Sexual stolons found in surface waters in June (June 1 1 , 

 1953) in Gulf of St. La\VTence, in July (July 1952, J. Rankin) and 

 during winter and spring (Sumner, 1913) in Massachusetts. 



Material examined. — Gulf of St. Lawrence (Bay of Chaleurs, 

 6 fathoms, June 11, 1953, female stolons), Massachusetts (Vineyard 

 Sound, in plankton, female stolon with egg sac, Jul,y 1952, J. Rankin). 



Distribution. — Known only from sexual stolons. Gulf of f-U. 

 Lawrence, Massachusetts (Salem, Vineyard Sound, vicinity Woods 

 Hole). Surface waters to 6 fathoms. 



Autolytus prisinaticus (Fabriciiis, 1780) 



Figure 37d 



Proceraea qracilis Verrill, 1874a, p. 132, pi. 5, fig. 1. — -Webster and Benedict, 1887, 



p. 723. 

 Autolytus longisetosus Baillie, 1946, p. 474.— Miner, 1950, p. 298, pi. 97. 

 Autolytus prisinaticus Pettibone, 1954, p. 249, fig. 29a-6. — Grainger, 1954, p. 513. 



Description. — Stem form length up to 26 mm., width up to 1 mm., 

 segments up to 105; nuchal epaulettes short, rounded, may extend 

 partly on first setiger; second pair dorsal cirri similar in length to 

 lower pair tentacular cirri; body white, yellowish or pale gTecnish, 

 with three conspicuous longitudinal dark brown or black bands; the 

 middorsal band broader and less dense, continuing throughout tlio 

 length of body, the dorsolateral bands at the level of the bases of the 



569-457—63 10 



