NORWEGIAN OPISTHOBRANCHIATE MOLLUSCA 33 



strong denticles on each side; the lam. lat. have from 9 to 26. 

 In C. horealis there are about 8 small and regularly dimin- 

 ishing denticles on each side of the central cusp, and 9 — 13 

 ones in the lateral laminae; further, the teeth are of a weaker 

 structure and light yellowish in colour. 



C. horealis seems to be restricted to the boreal region of 

 the European coast. According to the above list of localities it 

 is distributed all along the Norwegian coast, from Vadsø to the 

 Kristianiafjord. On the Swedish coast it occurs as far south as 

 Torekov, Skåne, from where I have recorded it in 1907 under 

 the name of C. verrucosa. 



Coryphella verrucosa M. S ars. Moldøen, 150—200 f ms, 2 

 sps., max. 1. 22— Bergensfjord, 2 sps., max. 1. 8 (det. as 

 „Eolis branchialis var, verrucosa") — The forms which I stated 

 in 1907 as belonging to this species, are C horealis (cf. above). 

 On the Swedish coast the present species, is also represented, 

 since 1 have found one specimen (1. 5.3 mm) in Gujlmarn, 

 Bohuslän, at Smedjan, 20 m, shell gravel with Furcellaria and 

 Flustra (^%o 1909). In this specimen the oral tentacles were 

 equal in size to the rhinophores and the tips of the papillae were 

 white. The typical specimens of M. Sars were badly preserved; 

 it could only be seen that the papillae were short and crowded 

 (not arranged in clusters), which serves to distinguish it from 

 C. rufibranchialis : in the latter species, in addition, the anus 

 is situated more towards front. 



Favorinus albus Alder & Hancock. Botten, Rissen, 4 sps., 

 max. 1. 5— Bergensfjord, 3 sps., max, I. 5 — Kopervik, 1 sp., 

 1. 4.5— Sunde, Hardangerfjord, 1 sp., 1. 9.5 — Rennesø, 4 sps., 

 max, 1. 5— Farsund, 1 sp., 1. 4.5 — Korshavn, 1 sp., 1. 4.5, 



Facelina drummondi Thompson. Florø, 6 sps,, max. 1. 18 

 (one sp. had carried a parasitic copepod, „Doricola agilis 

 Leydig'S according to a note on the label) — Farsund, 1 small 

 sp, — Kristianiafjorden, .Rosekollen (Kiaer Nov, 1915), 15 sps,, 

 max. 1. 19. 



Nyt Mag. f. Naturv. LX. 1922. 3 



