34 NILS ODHNER, NORTHERN AND ARCTIC INVERTEBRATES. III. OPISTHO BRANCH! A ETC. 



Faceliiia Alder & Hancock 1855. 



I. Rhinophores with 20 — 30 small rings of uniform size; papillae nearly cylindrical, 

 covering the whole back in 15 — 18 rows, of which 7 in the first, 5 in the 2nd 

 cluster; on each side 4 — 6 clusters. Colour pale reddish; rhinophores yellow; 

 liver-processes yellowish red to brown, near their end a triangular white spot and 

 above it the white cnidocyst. Teeth of the radula with 9 denticles on each side. 

 L. to 35 mm. F. Drummondi (Thompson 1843). 



PL III fig. 27. 



II. Rhinophores with strong laminae all around. 



A. Rhinophores with 7 — 8 wide rings alternating with smaller ones; gills in (i — 7 clusters, cylindrical; the 

 foremost groups, with 20 — 30 each, united behind the rhinophores. Colour white or reddish: papillae 

 red with blue lines and white tips. Teeth with 7 — 8 denticles on each side. I,. 25 mm. 



I'', coronata (Forbes 1839). 



Ii. Gills in 4 clusters, thin and filiform, sometimes nearly half as long as the body. Colour pale rosy, 

 gills light yellowish brown, the rhinophores darker, the oral tentacles rosy: all the processes with white 

 tips. Teeth with 7 denticles on each side. L. 12 mm. F. auriculata (Müller 1806). 



Fiona Alder & Hancock 1851 a . 



Papillae linear-conical, irregularly scattered over the sides of the back; oral ten- 

 tacles linear, the smooth rhinophores. Colour pale yellowish with a brilliant me- 

 tallic lustre; papilla? brown with bluish white tips, their membrane reddish. Teeth 

 of the radula with 6 — 7 denticles on the sides of the central spine. L. about 60 mm. 



F. marina (Forskäl 1775) nobilis Alder & Hancock 1851 \ 



Aiitiopa Alder & Hancock 1848. 

 Janus Verany 1844.' 



Papilla 1 numerous, inflated, very close-set at the sides of the body ; rhinophores 

 obliquely laminated, united by a crest at the base ; oral tentacles very short, digiti- 

 form ; head narrow. Body yellowish, transparent, papillse of the same colour, liver- 

 processes brown, at the tip forked, apices of the gills bluish. Radula 40.1.40. L. 

 about 30 mm. A. cristata (Delle Chiaje 1841). 



Hero Lüven 1855. 

 Cloelia Loven 1844.- 



Papilla^ 7 on each side, the first before the rhinophores, dichotomically branched; 

 in front of the head a distinct velum, concave in the middle. Colour yellowish with 

 diffuse white dots, a white median line on the back and one at each side; papillae 

 yellow. L. 17 mm. 



H. formosa (Loven 1844) = Cloelia trilineata M. Sars 1850. 



PI. Ill tigs. 30— 32. 



1 The name Janus was employed by Stevens in 1835 for an Hymenopterous insect. 

 - The name Cloelia was employed by Kitzinger in 1826 for a snake. 



