142 BIOLOGICAL SURVEY OF 



POLYDORA BOSC 



P. ciLiATA (Johnston). (Fauvel, 1927, p. 49, fig. 16i-p.) 

 Abundant on rocks at low tide and dredged from mixed bot- 

 toms to 220 feet. This species covers empty shells with its 

 intricate tunnels and seems to favor scollop shells and shells 

 inhabited by hermit crabs. It also builds its tubes in sheltered 

 spots among the rocks at low tide. Sexually mature speci- 

 mens may be found throughout July and August. The intes- 

 tine is infected with an acephaline gregarine. Stations : D 13, 

 15, 34, 39, 42, 54, 58, 60, 64, 68, 71, 75, 84, 94, 96, 144; S 4, 10, 

 12, 14, 25, 26, 39. 



P. coNCHARUM Verrill. (Verrill, 1879, p. 174; 1885a, pi. 43, 

 fig. 186.) This species inhabits tubes constructed on and in 

 empty shells on various bottoms from 26 to 68 feet. Abun- 

 dant at D 43. Stations : D 13, 43, 45, 51, 53, 55, 56, 61, 69, 71. 



P. GRACILIS Verrill. (Fig. 33.) Verrill, 1879, p. 174.) An 

 uncommon species taken on mud and blue clay from low water 

 to 220 feet. Stations : D 13, 15 ; S 11. 



Fig. 33 Polydora gracilis, typical large hooks. 



P. QUADRiLOBATA Jacobi. (Fauvcl, 1927, p. 54, fig. 18 1-r.) 

 The tubes are built on stones and old Pecten shells. Abun- 

 dant at D 92. Stations : D 72, 92, 94, 95. 



