68 NILS ODHNER, NORTHERN AND ARCTIC INVERTEBRATES. V. PROSOBRANCHIA. 1 DIOTOCARDIA. 



1868) 1 sp., h. 2.7. — Waygat Islands, 60 fms, clay (1861) 4 sps, max. h. 2.5. — 

 King Charles Land, 78° 50' N., 27° 39' E., 20 m, fine reddish yellow clay, bottom 

 temp. +0.2° 1898) 1 sp., h. 2.7; ap. 1.5; d. 3.i. — D:o, Bremer Sound, 100-110 

 m, fine clay with big stones, Biloculina sparse, bottom temp. —1.46° C^/s 1898) 4 sps, 

 max. h. 2.1. — ■ Dio, Swedish Foreland, 10 — 16 m, fine blackish-gray sand, stones, 

 clay, algse ("/s 1898) 3 sps, max. h. 2.8. 



Iceland (Odhner 1910). Dimensions: Öfjord, h. 3; ap. 1.5; d. 3; wh. 5, 

 Fig. 38. 



Greenland (Posselt & Jensen 1899). Dimensions: Proven, h. 4.3; ap. 2.2; 

 d. 4.3; wh. 4%, Fig. 40. — Upernivik, h. 3; ap. 1.5; d. 3.2. — Further: Kingitok, 

 73° 17' N., 56° 10' W., 27 m, hard stony bottom (E. Nilson 1894) 1 sp., d. 1.9. 



— Cape Dudley Digges, 30—40 m, mud (E. Nilson '/t 1894) 10 sps, max. d. 3. 



Variation of the radula (cfr. PI. 6 fig. 6): This — like the shell — is very 

 constant for different districts, being of the formula 40—50 .0.5,1.5.0. 40 — 50. 

 There is no transitory lateral tooth. The central and outer median teeth are fur- 

 nished with about 6 strong denticles on either side. The tooth outside the 5th me- 

 dian one differs from the others by having comb-like denticulation restricted to 

 its outer margin. Its denticles are denser, finer and blunter than those of the median 

 teeth, in this respect agreeing with the outmost teeth or lamellae, to which it there- 

 fore must be reckoned. On the 6 first of these a denticulation is evident, but on the 

 following it disappears. The outermost lamellse are very long and pin-shaped. 



In its form this radula shows agreement with Margarita in its great number 

 of median teeth and lamellae, but differs from the latter by the denticulation of the 

 lamelke occuring only in their outer margin and by the absence of a lateral tooth 

 mediating between lamellae and median teeth. 



General Distribution: 



Greenland to 300 fms (Posselt & Jensen 1899). — Iceland (Odhner 1910). ~ 

 Spitzbergen, Norwegian Islands, 115—146 fms (Friele 1879); Stor Fiord, 20 m (Kni- 

 powilsch 190P). — White Sea (Herzenstein 1893). — Parry Islands (Sutherland 1852). 



— Behring Sea (Krause 1885). Puget's Sound (Carpenter 1864). Depths 10—300 

 fms. Sand, stones, clay, algae. 



Solariella laevis Friele 1886. 



Distributiou: North Atlantic, W. of Norway, 300 — 350 fms, Norwegian North-Atlantic Expedition St. 

 124 and 173 b (Friele 1886). 



