KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 50. N:0 5. 



41 



Iceland (placed by Odhner 1910 in Lunatia groenlandica): Thistilfjord, 10 — 16 

 fms, sand, clay, 6 sps, max. h. 15.7; ap. h. 12,6; br. 13.4; ap. br, 7; iimb. 5.8; sut. 3.4; wh. 

 5 Va; an otlier sp, h. 14.7; ap. h. 12; br. 13; ap. br. 6.6; umb. 5; sut. 3.2; wli. 5; the smallest 

 sp. h. 5.5; ap. li. 4.3; br. 5; ap. br, 2.o; nmb. Le; sut. 1; wh. 3 V2 (Fig, 10), — ^ Raufarhofn, 

 25 fms, 2 sps, max, li. 26.8; ap. h. 20; br. 22.7; ap, br. 11. 3; umb. 9,6; sut, 8,7; wh, 5 ^4 

 (Fig, 11). — Siglafjord, 12 fms, 1 sp,, h, 4, 



Limits of Formål Variation. 



Mossel Bay, 45 sps measured: 



h. of sliell . • • 

 h. of aperturo . 

 br. of shell . . 

 br. of aperture . 

 lip to iimbilicus 

 lip to suture . - 

 whorls 



5—6 

 4.2—5.5 

 4.5—6.2 

 2.5—3.3 

 1.7—2.3 

 about 0.5 — 1.1 

 3-3V3 



7—8 

 6—7.5 

 6.5—8.2 



3.4—4.4 

 2.5—3.3 

 0.9—1.5 



372-3^4 



9—10 

 7.5—8.9 

 8 3—10 

 4. .5 — 5.4 

 3.2—3 7 

 1.3—1.9 

 4 



11- 



-12 



9.2- 



-10.4 



10- 



-11.6 



5.2- 



-6.3 



3.8- 



-4.r, 



1.7- 



-2.4 



about 4 1 



Advent Bay, 10 sps measured (values approximate) : 



b. of shell . . . 

 b. of aperture . 

 br. of shell . . 

 br. of aperture 

 lip to umbilicus 

 lip to suture . . 

 whorls 



h. of shell . . . 

 h. of aperture . 

 br. of sliell . . 

 br. of aperture 

 lip to umbilicus 

 lip to suture . . 

 whorls 



about 6.2 — 7.1 



6.4—7.4 



» 3.5 — 4 



» 2.5—3.2 



» 2.2—2.6 



» 37, 



9—10 

 7.7—9 

 8.1—9 

 4.4—5 

 3.2—4 

 1.5—2 

 4 



11- 

 9.3- 

 9.3- 



-12 



-10.7 

 -10.5 



5.3—63 

 3.9—4.9 

 1.7—2.5 



4-f- 



Iceland, 8 sps measured (values approximate): 





5—6 





about 4.3- 



-5 



» 



4.6- 



-5.8 



» 



2.4- 



-3.2 



» 



1.4- 



-2.2 



» 

 » 



0.8- 

 3'/. 



-1.3 



5.4—6.8 



6.3—7.7 

 3.2—4.3 



2.2—3 



1.2—2.1 



3^/4 



9—10 



7—8.5 



7.8—9.2 



3.9—5 



3—4 



1.5—2.4 



4 



11—12 



8.7—10 

 9.5—10.8 

 4.8—5.8 

 3.8—4.8 

 1.9—2.9 

 about 472 



14—15 



11.6—12.7 



12.5—14 



6.5—7.5 



4.7—5.6 



2.5—3.2 



about 472 



14—15 



11.6—13.3 



11.4—13 



6.8—7.7 



5.1—6.3 



2.1—3.1 



4'/, 



14—15 



11.2—12.5 



11.9—13.4 



6.1—6.9 



4.8 — 5.7 



2.9—35 



By comparing the above tables we see plainly that some constant differences are 

 present between the specimens from the three localities. In the Iceland shells the breadth 

 of the shell and the height of the aperture are somewhat greater than in those from Mossel 

 Bay, and also the breadth of the aperture is shorter, but the distance from lip to suture 

 is considerably higher. The Advent Bay form is intermediate, as the breadth is by com- 

 parison smaller, though the height of the aperture is greater, than in Mossel Bay; in 

 the distance from lip to suture and to umbilicus they vary within the same limits. 



The number of whorls in specimens of the same height is also different in the three 

 localities. It is, however, not easy to determine it exactly as the spires in shells from 

 Spitzbergen are usually worn away. In order to find out the size in its relation to the 



K. Sv. Vet. Akad. Handl. Band 50. N:o 5. " 6 



