Plate III. 



Fig. r. Modiola modiolus L., young. 



a. A left valve from the inner side, x 3, i. Iceland. 



b. The anterior end of the same valve, x 7. 



— 2. Modiola phaseolina Phi lip pi. 



a. A left valve from the inner side, x 1. Iceland. 



b. The anterior end of the same valve, x 8. 



— 3. Idas argenteus Jeffreys. 



a. A left valve from the outer side, x 6 1 /,. S. of Iceland, 975 fm. (Ingolf St. 67). 



b. A left valve from the outer side, without the hairy periostracum. x 12. 



c. A specimen from the upper side, x 12. 



d. Hinge of right valve, x 10. 



e. Hinge of the same. X 20. 



4. Modiolaria discors L. var. Imvigala Gray. 



a. A specimen from Spitzbergen. x 1. 



b. Dorsal view of the same, x 1. 



— 5. Modiolaria discors L,. var. substriata Gray. 



a. A specimen from West Greenland, x 1. 

 h. Dorsal view of the same, x 1. 



c. A part of the middle area to show its "smooth" (simply striated) surface, x 5. 



— 6. Modiolaria discors L,. 



a. A specimen from Denmark, x 2. 



b. Dorsal view of the same, x 2. 



— 7. Modiolaria cor ruga fa St imp son. 



a. A specimen from Spitzbergen. x i 1 ... 



b. A specimen from West Greenland (Fiskensesset). x 1 1 ... 



c. Dorsal view of the same, x i'/z- 



d. A part of the middle area to show its shagreen-like wrinkled surface, x 5. 



— 8. Modiolaria faba (Muller) Fabricius. 



a. A specimen from West Greenland (Ritenbeuk). x 1. 



b. Dorsal view of the same, x 1. 



c. Interior of the right valve, x 1. 



— 9. Cardinal fascia I it 11 1 Montagu. 



a & b. A specimen of the short, strongly veutricose form, x 1-' ;',. Faeroes, 20—30 fm. 

 c & d. A specimen of the somewhat elongated, not much tumid form, x 3. West Iceland 

 (Gnundarfjordr), ca. 12 fm. 



e. A specimen with tubercles not only on the anterior and posterior area, but also on the 

 middle area, x 6. West Iceland (Gnundarfjordr), ca. 12 fm. 



f. That form which was confused by Morch with C. edule h. x i 2 / v Faeroes. 



g. The same half from in front, x 3. 

 h. The same half from behind, x 3. 



i. A specimen with an obliquely cordiform contour, x 8 x / 2 . Faeroes, 135 fm. 

 k. A specimen half from behind showing an intercostal sculpture in the form of a fine 

 pricking, x 5. West Iceland (Gnundarfjordr), ca. 12 fm. 



— 10. Cardium ciliatum Fabricius. 



A very young specimen, x ro'/z- East Iceland (Bakkafjordr), 52—43 fm. 



— 11. Card 1 it 111 cell ina fit 11/ I v . 



A very young specimen, x io I / 2 . South Iceland, 17 — 23 fm. 



— 12. Car.dium (Serripes) groenlandicum Chemnitz. 



a. A very young, strongly sculptured specimen, x 6. West Greenland (Godthaabs Fjord). 



b. A ver) young, comparatively smooth specimen, x 5. West Iceland (Gnundarfjordr), 10 fm. 





