668 DR. GWYN JEFFREYS ON THE MOLLUSCA OF THE [NoV. 14, 



Distribution. C. Croisic {Cailliaud), C. Breton (de Folin), Spain 

 (McAndrew and others), Mediterranean and Adriatic (Poli and 

 others) to ^gean (Forbes) ; 5-20 fms. 



(^ 5. Chiton cinereus, Linne. 



C. cinereus, L. S. N. p. 1107 : B. C. iii. p. 218; v, p. 198, pl.lvi. 

 f. 2. 



'Lightning' Exp. St. 4, 5. 



'Porcupine' Exp. 1869: St. 2, Lough Foyle. 1870: Atl. 36 

 (plate). 



Distribution. Greenland (Fabricius) ?, Iceland, Faroe L, Finmark 

 to Vigo Bay; 1-150 fms. Apparently not Mediterranean nor 

 Adriatic. 



Fossil. Pliocene : Sicily {Monterosato and Tiberi), Post-tertiary : 

 Norway and Scotland ; 0-80 ft. 



One of the synonyms is C. asellus of Spengler. 



6. Chiton arcticus, G. O. Sars. 



Lejiidopleurus urcticus, G. O. Sars, Moll. reg. arct. Norv. p. 112, 

 t. 7. f. 7, a-h. 



' Lightning ' Exp. St. 3, 4. 



Distribution. Spitzbergen, Greenland as C. cinereus (ilf. Sars) 

 probably, Finmark and Vadso {G. O. Sars); 20-100 fms. 



Fossil. Post-tertiary : Norway, as C. cinereus {M. Sars) probably. 



This differs from the white variety of C. cinereus in its com- 

 paratively greater length and more raised or arched form, in the less 

 distinct or regular catenation of the granules which cover the sur- 

 face, and in the prominence of the lateral areas. 



i, 7. Chiton alveolus, M. Sars. 



C. alveolus (Sars MS.), Loven, Ind. Moll. lit. Scand. occ. hab. 

 p. 27. 



Lepidopleurus alveolus, G. O. Sars, Moll. reg. arct. Norv. p. 110, 

 t. 7. f. 3, a-c. 



' Porcupine ' Exp. 1870: Atl. St. 1. 



Distribution. Norway, Bay of Biscay (' Travailleur ' Exp.) ; 

 120-664 fms. 



The late Professor Sars, in his remarks on the occurrence of 

 animal life in the depths of the sea, 1868, referred this species of his 

 to C. cancellatus; but C. alveolus is larger and longer or more 

 oblong, and it has a different sculpture. 



' 8. Chiton rarinota', Jeffreys. (Plate L. fig. 1.) 



Shell oblong-oval, arched, rather thin and glossy : plates broader 

 in the middle than at the sides ; lateral areas indistinct : sculpture 

 consisting of white tubercles, which are few in number and irregularly 

 scattered ; these are round in the middle of the shell, but become 



' Haying few marks. 



