96 ROYAL SOCIETY OF CANADA 
equally abundant. It varies a good deal in colour, as does J. interstinctus 
also, but is usually much darker than that species. 
An exceptionally pale specimen was named Leptochiton punctatus, by 
Mr. Whiteaves, under the supposition that it was a new species. 
ISCHNORADSIA, Shuttleworth, 
338. IscunoRADSIA MeErTENSII, Middendorff, sp. 
Chiton Mertensii, Midd., Bull. Acad. Sci. St. Peters., vol. vi., no. 8. p. 118 (April, 1847); 
and Mal. Ross., pt. 1, p. 125, no. 16, pl. xiv., fig. 1-3 (1847). 
This species is found, but not plentifully, in most localities examined 
from Victoria to the Queen Charlotte Islands. 
It is most frequently obtained by dredging, but is sometimes found 
between tides. Some very large specimens were collected by myself on 
the rocks at low water at Salt Spring Island. 
339. ISCHNORADSIA TRIFIDA, Carpenter, sp. 
Trachydermon trifidus, Cpr., Rept. Brit. Assoc., 1863, p. 649 (August, 1864); and 
Proc. Acad. Nat. Sci. Phila., 1865, p. 60. 
The type specimen of this rare species was collected by Dr. Ken- 
nerley in Puget Sound. Two specimens were obtained by Dr. Dawson, 
one at the mouth of Cumshewa Harbour in twenty-nine fathoms, and 
the other in Queen Charlotte Sound. 
Quite lately Dr. Newcombe has found one or two specimens near 
Victoria. These are all the British Columbian specimens I have neard 
of, and to the north of us J. trifida is equally rare. 
NUTTALLINA, Carpenter. 
340. NUTTALLINA SCABRA, Reeve, sp. 
Chiton scabra, Reeve, Conch. Icon., Mon. Chitons, pl. xvii., fig. 106 (1847). 
Dr. Kennerley is said to have collected one young living specimen 
in Puget Sound. Dall gives the distribution of the species as ‘‘ Vancou- 
ver District, south to California, probably in the southern islands of 
Alaska ; at and above high-water mark, in crevices of the rocks ; at 
Monterey abundant.” 
I have seen numerous Californian specimens but have never found or 
seen a British Columbian example. 
MOPALIA, Gray. 
341. MoPALIA CILIATA, Sowerby, sp. 
Chiton ciliatus, Sowerby, Conch. Ill., p. 79, 1838 
= CO. muscosus, Gould, Proc. Bost. Soc. Nat. Hist., vol. ii., p. 145 (July, 1846); 
and U. S. Expl. Exped., Mollusca, p. 313, fig. 436 (1852). 
var. Hindsii, Gray, Proc. Zool. Soc. London, 1847, pp. 69 and 169. 
