1888 - 89 .] Mr John Rattray on the Genus Coscinodiscus. 587 
C. cribrosus. Tru. and Witt, Jeremie Diat ., p. 14, pi. ii. fig. 25. 
— Diam. -06 to ’08 mm. Surface fiat. Central space irregularly 
angular, small. Markings rounded, increasing slightly from the 
central space for about \ of the radius, thence subequal to the 
distinct band adjacent to the border, upon this band punctiform ;. 
towards the centre 3J, at the semiradius 3, on the marginal band 6, 
in -01 mm.; rows straight, secondary oblique rows inconspicuous. 
— Sch., Atl ., pi. Ixiv. fig. 11 (no name). 
Habitat. — Jeremie deposit (Truan and Witt); Moron deposit 
(Schmidt). 
C. subdivicus. Tru. and Witt, Jeremie , Diat ., p. 14, pi. ii. fig. 
13. — Diam. *05 mm. Surface almost flat. Central space and 
rosette absent. Markings rounded or obtusely angular, decreasing 
gradually from the centre to the border ; towards the centre 4 to 
4J (?) in -01 mm.; at the border punctiform ; rows reaching the 
centre few, those intervening shorter and less prominent, on a 
narrow band adjacent to the border, numerous. 
Schmidt has assigned this species to Adinocyclus , but Truan and 
Witt have failed to find a pseudonodule, and so justly unite it to 
Coscinodiscus. 
Habitat. — Jeremie deposit (Truan and Witt). 
C. undulatus. Cleve, Kongl. Sv. Vet.-Ak. Handl. Stockh., 1881,. 
No. 5, p. 20, pL v. figs. 60a, 60 b . — Diam. -0575 to -096 mm. 
Central space elongately elliptical, major axis ^ to i of diam., 2 to 
3 times minor, sometimes subcircular. Surface slightly convex or 
subplain at the centre; a distinct broad elevated zone about the semi- 
radius, with the inner edge less abrupt than the outer. Markings 
pearly, round, granular, increasing slightly from the central space 
to the elevated zone ; towards the centre 4, on the highest zone 4 ;; 
somewhat larger but more crowded on a narrow but distinct band 
adjacent to the border; again smaller, punctiform, about 6 in *01 
mm., interspaces hyaline. Border with its inner edge sometimes 
distinct, strise moniliform, 6 to 7 in '01 mm. 
Habitat. — Galapagos Islands (Weissflog ! Cleve !). 
C. bating omphalus. Cleve, Vega JExped., Vetensk. Jakttag . 
Stockh ., Bd iii., 1883, p. 489, pi. xxxviii. figs. 81a, 816. — Diam. 
