124 WHITEAVES ON MARINE INVERTEBRATA, ETC., 



yDENDRONOTUS PURPUREUS ? Bergh. Elk Harbour, one large and two small living 

 specimens. 



f SIPHONARIA THERSITES, Carpenter. Living and apparently not uncommon, at low tide, in 

 Johnstone Strait, on the east side of Queen Charlotte Sound ; on the north and 

 north-west coast of Vancouver Island, from Nahwitti Bar to Quatsino Sound, and 

 in Quatsino Sound. 



CADTJLUS ABERRANS. N. Sp. 



FIG. 2. Cadvlus aberrans. Side view of an average specimen, enlarged three diameters. 



Shell slender, moderately but distinctly curved, large and much elongated for 

 the genus, increasing very slowly but regularly in diameter, not distinctly (if at all) 

 swollen in advance of the middle, and very slightly and scarcely perceptibly con- 

 stricted immediately behind the aperture. Test extremely thin, surface polished, 

 very glossy and shining, smooth to the naked eye, but under a lens it is seen to be 

 marked with minute and transverse but somewhat oblique lines of growth. 



Length of an average, full-sized example, 13.5 mm. ; greatest breadth of the 

 same near the anterior end, 1.3 mm. 



Very abundant in Quatsino Sound at station No. 20. 



This little shell, which is nevertheless of large size for the genus, looks not 

 unlike an immature Dentalium, and, at first sight, specimens of it might be easily 

 mistaken for half-grown examples of D. pretiosum, Nuttall, which the Indians say 

 occurs at the same locality. It may, however, be distinguished from any Denta- 

 lium by its thin test and highly polished outer surface, though the swelling of the 

 shell in advance of the middle and the constriction behind the aperture, which are 

 usually marked characters in the genus Cadulus, are reduced to a minimum in this 

 species, and in most specimens are quite imperceptible. 



The writer has been informed by Mr. Ball that there are specimens of this shell 

 in the museum of the Smithsonian Institution at "Washington, which were collected 

 by Dr. J. G. Cooper at Catalina Island, California. 



- MOPALIA CILIATA, Sowerby. (Sp.) More or less abundant, living, at low tide, in Discovery 

 Passage, Johnstone Strait, the Goletas Channel, and Quatsiuo Sound. One living 

 specimen was dredged in Queen Charlotte Sound at station No. 18. 



, MOP ALIA LIGNOSA, Gould. Living, at low tide, on the north side of the Strait of Georgia, 

 in the Goletas Channel; and in Queen Charlotte and Quatsino Sounds. 



