2 NILS ODHNER, NORTHERN AND ARCTIC INVERTEBRATES. V. PROSOBRANCHIA. 1 DIOTOCARDIA. 
Iceland (ODHNER 1910), var. islandica. Dimensions: h. 4.5; ap. 2.9; d. 5.8; 
wh. 4'/4, Fig. 24. 
N. W. Atlantic: 52” 25 N., 52 12 W., 162 fms, loose elay mixed with sand 
(Lindahl "Yes: 1871)-2 shsjmax.; hd: cap. 245 did whh 4 Ve(vart belajEt 520 
N., 52” 19' W., 161 fms, elay, ,mixed,with sand, (Lindahl 35/st 187) sas tap: 
3.3; d. 7.7; wh. 4”/a (type, resembling specimens from Kara Sea, without trace of 
umbilical keel, but more depressed; determined by Posselt as M. groenlandica), Fig. 18. 
West Greenland (not observed by Posselt): Julianehaab, 25 fms, clay, among 
M. groenlandica (Amondsen Okt. 1861) 1 sh., h. 4.5; ap. 2.6; d. 5.6; wh. 4 '/« (var. is- 
landica). — Godthaab, 72 fms, sand, among M. cinerea (Amondsen July 1862) I1sp., 
h. 4.7; ap. 2.8; dr 67 wh. 4 fe (var. bella), Hig 340--7 Davis Strait, GSI 4SvENS 
53” 33 48" W., 48 fms, greenish clay (Lindahl '?/e 1871) 11 sps, max. h. 4.38; ap. 2.8; 
d. 6.4; wh. 4'/2 (var. multilirata, determined by Posselt as M. groenlandica), Fig. 
28, 29, 30. — Umanak, 200 fms, clay, among M. cinerea (Amondsen 1862) 1 sp., h. 
5.8; ap. 3; d. 7.1; wh. 5 (var. multilirata, untypical), Fig. 33. — Jakobshavn, 120 
fms, clay mixed with sand (Öberg !4/g 1870) 1 sh., h. 2.1; ap. 1.7; d. 2.9: wh. 4 (var. 
multilirata, determined by Posselt as M. cinerea). — Godhavn, 10—40 fms, mud ('/se 
1860) 1 sp., h. 5; ap. 2.5; d. 6; wh. 4'!/2 (var. multilirata, untypical with strong, 
broadly rounded riblets), Fig. 32. 
East Greenland: King Oscar's Fiord, S. of Ruth's Islands, ca 125 m, mud, 
sand, pebbles (''/s 1899) 1 sh., d. 1.9; wh. 3 (var. bella). 
Newfoundland Bank, the type: 46” 5 N., 51” 44' W., 56 fms, sand, shells (Lin- 
dahl: "9/8 11871) 3 :sps;i max; hj 6:4; ap. 35; od. 8; whae55; onythel whorlsiutupper, 
stronger, and 3 lower finer revolving ridges; over the strong uppermost ridge there is 
a trace of a finer one. 
Variation of the shell: 
| Kola Peninsula, Spitzbergen, h. | | 5—6 | 6—7 | | 9 |m max. 9.4 ( (Megll.n N:o > 1068) | 
Behring Sea etc.; ap. | 2.6—3.5 | 3-4 | 3.5—4.6 3.8—5.6 | 4.4—6 uns 5.1 
45 sps of forma typica d. | -5—6.8 | 5.6—7.6 | 6.5—38.9 | sa 1ILB] ONS 11.6 
| measured wh. | 4—4!/2 | 4!/4—5  |42/4—5 | about 5 | ör >5 
Specimens from BSpitzbergen have a smaller diameter of the shell than those 
from more eastern districts: their maximal dimensions are not so high (max. h. 7.5 
etc., Recherche Bay). 
Norway and Spitzbergen; h. 2.5 3—4 4—5 5—6 max. 5.7 7 (G sötäund). 
14 sps of var. bella ap. | 11 | LE Me RER SN 2 Dn 2.7 
| measured d. | 2.8 | d2—4.5 | 4.2—5.3 | 5—6.1 | 6.1 
Wwh.. |. Sia | AR be 4"/: ul about 5 5 | RO | 
Greenland; 106 2—3 | 3—4 4—5 5—6 max. 5.8 (Umanak) 
14 sps of var. multilirata ap. | 1.3—2 | 1.8—2.3 | 2.2—2.9 | 2.5—3.5 | 3 
measured d. | 2.6—4 | 3.8—5.2 | 4.6—06.7 6—8 | tin 
wh. | 3—3!/1 | 3!/2—4 | 4!/1—4'/2 | about 5 5 
