482 
Proceedings of Royal Society of Edinburgh. [sess. 
Habitat. — Arctic, Davis Straits ; Franz Josefs Land, H. Siberia ; 
Antarctic (Grunow) ; Davis Straits (Cleve and Moller !) ; Mascara, 
Cape Wankarema (Cleve ! Cleve and Moller !) ; Greenland 
(Cleve !). 
C. inclusus , sp. n. Sch., Atl ., pi. lvii, fig. 47 (no name). — Diam. 
about *07 mm. Central space distinct, rounded, slightly excentric. 
Markings rounded, granular, about 5 in ’01 mm., smaller towards the 
border ; rows fasciculate, those in each fasciculus parallel to the 
central radial row, non-apiculate. Border sharply defined, striae 6 
to 8 in ‘01 mm. 
Habitat. — Richmond deposit, Virginia (Schmidt). 
C. tuber culatus. Grev., Trans. Micr. Soc. Lond. 1861, p. 42, pi. iv. 
fig. 6. — Diam. -0375 to *0975 mm. Surface almost flat. Central 
space irregular, small. Markings around the central space minute, 
rounded, granular; beyond this polygonal 4J in ‘01 mm., subequal 
to the zone of the apiculi ; at the border 6 in *01 mm.; rows radial 
or obscurely fasciculate, straight ; apiculi distinct placed between 
the fasciculi. Border striae delicate, 8 to 10 in '01 mm. — Sch., Atl ., 
pi. lvii. fig. 42 ; Grun., Denk. Wien. Ak., 1884, p. 82. 
This species cannot be united with Aulacodiscus, as suggested, 
with some doubt, in the second edition of Habirshaw’s Catalogue, 
§ Coscinodiscus. Small specimens in Weissflog’s collection have 
been distinguished as forma minor , but these are quite normal. 
Distinguished from C. subtilis by its larger markings and more 
robust apiculi. 
Habitat. — Barbados deposit (Greville ! Hardman ! Firth ! 
Cleve !) ; Chalky mound, Barbados (Weissflog ! Firth !) ; Cam- 
bridge deposit, Barbados (Firth ! Johnson ! Hardman !). 
Var. Monicas. Grun. ibid., p. 82, pi. iii. (C), fig. 29. — Diam. 
*0625 mm. Markings 3 to 5 in *01 mm., smaller close to the 
border ; a few rows in each inconspicuous fasciculus ; the apiculi 
nterfasciculate, more evident. — C. tuber culatus, Grev. var. ? Sch., 
Atl., pi. lvii. figs. 40, 41. 
The markings in the Barbados valves are larger than those in 
Sta Monica specimens. According to Schmidt, there are no pro- 
