178 BIOLOGICAL SURVEY OF 



Ischnochitonidae 

 ToNicELLA Carpenter 

 T. MAEMOEEA (Fibricius). {Chiton marmoreus Fabricius, 

 1780, Fauna groenlandica ; Chiton fulminatus Couthouy, 1838, 

 Boston Jour. Nat. Hist., vol. 2, p. 80, pi. 3, fig. 19 ; T. marmorea 

 Pilsbry, 1892, Manual Conch. Ser. 1, vol. 14, p. 41, pi. 10, 

 figs. 8-15.) Common in tide pools and dredgings. Reported 

 from Casco Bay, Massachusetts Bay. Common as far as 

 Greenland, low-water mark to 50 fathoms. One small speci- 

 men from Hudson Bay. 



Trachydermon Carpenter 



T. ALBUs (Linne). {Chiton albus Linne, 1767, Syst. Nat. 

 ''Oceano Islandico." Chiton albus Gould, 1870, p. 263, fig. 

 525.) This species is found on rocky and hard clay bottoms. 

 Is a food for haddock, being found in their stomachs. Sta- 

 tions : D 19, 95. Reported from Casco Bay, Isle of Shoals. 

 Common and distributed as above. 



T. RUBER (Linne). {Chiton ruber Linne, 1767, Syst. Nat. 

 ''Oceano Septentrionali," Chiton ruber Gould, 1870, p. 260, 

 fig. 523.) This is the common species and is found every- 

 where clinging on the rocks from tide pools to the hard bot- 

 toms of the Bay. Is very partial to the hard blue clay bot- 

 toms. Stations: D 39, 43, 63, 87, 95, 125, 130; S 11, 12, 3L 

 Reported as 'occasional' from Woods Hole and one specimen 

 dredged by that survey ; Eastport, Casco Bay, off Watch Hill, 

 R. I., off New London. Grand Manan abundant. See Whit- 

 eaves, p. 155. 



Acanthochitidae 

 Amicula Gray 

 A. VESTITA (Broderip and Sowerby). {Chiton vestitus 

 Broderip and Sowerby, 1829, Zool. Journ ''Oceano Arctico"; 

 Amicula emersonii Gould, 1870, Inv. Mass., p. 264, fig. 527; 

 Amiclua vesiita Pilsbry, 1893, Manual Conch. Ser. 1, vol. 15, 

 p. 43, pi. 8, figs. 23-26.) Reported by Blaney; Casco Bay, 

 Massachusetts Bay, from fish. ''Widely distributed but ap- 

 parently very local (in Canada)." Whiteaves, 



