800 MISS HELEN PIXELL OX 



12. Spirorbis asperatus Bush (3), 1905 ; Sitka. (PI. LXXXIX. 



fig. 12.) 



Specific characteristics : — 



1. Collar setse witli simple blades. 



2. Operculum without brood-pouch. 



3. Calcareous plate of operculum thin, with large lateral wings 



on its talon. 



4. Some setae of 3rd fascicle short fringed sickles (fig. 12), 



others with long narrow blades. 



On an old Serpulid tube inhabited by a hermit crab. One 

 specimen only. The opaque sinistral tube shows conspicuous 

 growth-lines, and the whorls are somewhat piled on one another. 



There are 12 or 13 reddish gills nearly hidden by the high 

 collar, above which the operculum projects for some distance. 

 The alimentary canal was greenish and the ova along the dorsal 

 surface salmon-pink. The abdomen consisted of about 20 

 segments. 



13. Spirorbis validus Yerrill (26), 1874. (PI. LXXXIX. fig. 13.) 



.S'. verruca Levinsen (10), 1883, figs. -j-Caullery & Mesnil 



(5), 1897 ; Moore (17), 1902. 

 S. validus Bush (3), 1905. 



Specific characteristics : — 



1. All thoracic setse with long, finely serrated, narrow blades 



(fig. 13). 



2. Operculum with brood-pouch. 



3. Opercular plate (Bush (3), pi. xliv. figs. 11-14). 



4. Branchiae 13. 



On old shells of Balanus iiubilus from Dodds Narrows, 15 to 

 28 fathoms. 



The tubes were smooth, sinistral, and opaque, measuring 3 mm. 

 in diameter. The operculum was colourless and transparent, 

 with a large sac-like brood-pouch which was, however, empty in 

 specimens collected on September 1st. The gills and thorax were 

 of a bright orange-red colour, the rachises being thick with a double 

 row of small pinnaj extending inwards at right angles. Abdomen 

 with 25 segments having a few setse, some being somewhat 

 geniculate, others small hooks (Bush, pi. xxxvii. figs. 5 & 6). 



14. Spirorbis. MEDius, sp. n. (PI. LXXXIX. figs. 14«-14e.) 

 Specific characteristics : — 



1. Some collar setse with shallow posterior notch (fig. 14 a). 



2. Operculum without brood-pouch. 



3. Calcareous plate of operculum very large and of character- 



istic shape (figs. 14 c & d). 



4. Some setse of 3rd segment serrated bladed sickles (fig. 14 e). 



From Channel just outside Departure Bay. Large flat tubes 



