1888 - 89 .] Mr John Rattray on the Genus Coscinodiscus. 469 
C. pulchellus. Grev., Trans. Micr. Soc. Lond ., 1866, p. 3, pi. i. 
fig. 7. — Diam. from ’06 to ’09 mm. Surface convex. Central space 
absent. Markings mostly hexagonal, 2 1- in ’01 mm., decreasing 
gradually to the border, at wide irregular intervals narrower and more 
distinct areolae are scattered irregularly on the middle J, those forming 
the outermost band longer but not wider, their long axis radial. 
Border sharply defined ; striae distinct, remote, 4 in *01 mm. 
This species approaches G. splendidus, Grev., and C. macraeanus , 
Grev., but is distinguished from the former by the striated border 
and from the latter by the marginal apiculi. Grunow, who has 
justly reduced the genus Cestodiseus to a section of Coscinodiscus 
(Pant., Fossil. Bacil. Ung ., p. 73), names Cestodiseus pulchellus , 
Grev. (Trans. Micr. Soc. Lond., 1866, p. 123, pi. ii. fig. 5), Coscino- 
discus pulchellus , though distinct from Greville’s Coscinodiscus 
pulchellus, which was published somewhat earlier. Coscinodiscus 
(pulchellus, var.?) hirtulus, Grun. (Van Heurck, Syn. IHat. Belg., pi. 
exxvi. fig. 3), and Coscinodiscus pulchellus, var. Trinitatis, Grun. 
(Van Heurck, ibid., pi. exxvi. fig. 4), are related to Greville’s 
Cestodiseus pulchellus. 
Habitat. — Cambridge deposit, Barbados (Johnson !).* 
C. zonulatus, sp. n. ? Sch., Atl., pi. lix. fig. 6. — Diam. -024 mm. 
Central space and rosette absent. Markings regularly angular, 
subequal, 10 in *01 mm.; adjacent to the border a distinct band 
of large imperfect areolae, with inner edge absent, and outer slightly 
convex outwards, about 5 in *01 mm. Border sharply defined about 
of radius broad, hyaline. 
Habitat. — Cape of Good Hope (Schmidt). 
C. aphrastos, f sp. n. Sch., Atl., pi. lxv. fig. 18. — Diam. -0755 
mm. Central space and rosette absent. Markings pentagonal or 
hexagonal, about 1J in ’01 mm.; at wide intervals, a few minute 
areolse interspersed. Central papillae absent. Border prominent, 
sharply defined, hoop-like; striae robust, about 1J in ’01 mm. 
Habitat. — Campeachy Bay (Griindler). 
C. concavus. Greg., Trans. Roy. Soc. Edin., 1857, pi. x. fig. 47. 
— Diam. ’07 to ’2375 mm. Surface subplain, with a prominent 
In the collection of Dr Greville. 
t &<f>pa.o-Tos, unexpected. 
