20 



NILS ODIINER, NORTHERN AND ARCTIC INVERTEBRATES. III. OPISTHOBRANCHIA ETC. 



B. Lips armed with 



1. small staves: tentacles digitif orm ; foot incised in front; radula oo.O.oo 

 (subfam. Discodoridina?). Gills simple-pinnate, 10, small; penis unarmed; 

 the inner laterals solid, less hamate, the outer ones thinner with longer 

 hooks, divided in the cusps Rostanga Bergh. 



2. small hooks ; tentacles broad, flattened, triangular ; foot not incised in 

 front; radula oo.l.oo (subfam. Cadlinina?). Gills tripinnate, 5, small; penis 

 with series of hooks; laterals hamate, serrated on the outer margin 



Cadlina Bergh. 



Bathydoris Bergh 1884. 



Body (in alcohol) nearly gelatinous, on the back almost transparent. Rhinophores and tentacles brown : 

 gills and outer genital organs orange-coloured: toot dark-crimson. L. 93 mm. B. ingolfiana Bergh 1899. 



Archidoris Bergh 1878. 



I. Papillae wart-like, of varying size, irregularly distributed. Colour yellowish brown, 

 marbled with greenish, reddish or brownish spots. L. up to 70 mm. 



A. tuberculata (Cuvier 1804). 



PI. II tig. 8; PI. Ill fig. 6. 



II. Papilla? wart-like, of varying size; the middle of the back with three longitudinal 

 series of larger tubercles. Colour light reddish, towards the mantle-margin yellow. 

 L. about 50 mm. A. nobilis (Loven manuscr.). 



PI. I ligs. 14—18. 



Joruima Bergh 1876. 



Papilla? not wart-like, but of uniform breadtli or broader towards the end, fine 

 and densely set. Colour yellowish, sometimes with dark spots; rhinophores brown. 

 L. to 40 mm. J. Johnstoni (Alder & Hancock 1845 a ). 



Aldisa Bergh 1878. 



Papillae conical. Colour whitish with (dose light dots; rhinophores and gills yellowish. Liver bluish 

 showing through the skin. L. about 20 mm. A. zetlandica (Alder & Hancock 1855). 



Platydoris Bergh 1877. 

 Papilla? of varying size, soft, wart-like ; mantle pale yellowish, spotted with 

 brown, the underside lemon-coloured with brown dots and anastomosing lines; rhino- 

 phores yellowish ; gills 6—8, marbled with brown and white ; laterals of the radula 

 smooth. L. 42 mm. (in the collections) P. planata (Alder & Hancock 1846 a ). 



PI. I tigs. 19—20. 



Kostaiisa Bergh 1881. 



Papilla? small, close, square. Colour red with black dots; rhinophores yello- 

 wish, gills red. L. c. 12 mm. R. coccinea (Forbes 1843) 



Cadlina Bergh 1878. 



I. Back with wart-like papilla?; radula 22.1.22. Colour milk-white with one series 



