1888 - 89 .] Mr John Rattray on the Genus Coscinodiscus. 557 
deposit (O’Meara !) ; Baltic Sea (Van Heurck !) ; Teignmouth 
Grove !) ; Peruvian guano (Cleve ! Macrae !) ; Sta Monica deposit 
(Cleve and Moller !) Sta Maria deposit (Grove !) ; Davis Straits, 
Patagonia ; Nottingham deposit, Md. (Cleve and Moller !) ; Moller’s 
Elbe material (Cleve!); Patagonia, 1375 fathoms, H.M.S. 
Challenger (Cleve !) ; Faroe Channel (Grove !) ; west coast Florida, 
U.S. Survey (Febiger !) ; Yeddo, Bohuslan, Kusu, Pabillan de Pico 
guano ; Greenland ; Successful Bay, Kerguelen (Cleve !). 
C. Jloridulus. Sch., MfZ., pi. cxiii. fig. 16, a , b, c . j — Diam. 
•1135 mm. Surface flat. Central space irregular, small, about 
2 ^- of diam. broad. Markings polygonal, largest round the central 
space, thence decreasing slightly outwards ; towards the centre 4, 
towards the border 6, in *01 mm.; minute puncta at the origin of 
the shorter rows ; rows substraight ; secondary oblique decussating 
rows evident ; minute apiculi at angles of areolae (seen in oblique 
aspects). Border narrow. 
Distinguished from C. obscurus by the size of the markings and 
character of the border. 
Habitat . — Sta Monica (Schmidt). 
C. incequisculptus, sp. n. Roundly elliptical; major axis *175 
mm., about l-Jy times minor. Surface slightly convex towards 
the centre. Central space absent ; rosette distinct. Markings 
hexagonal, and increasing slightly outwards to about the semi- 
radius, 4 to 4J in ‘01 mm. in radial rows ; beyond the semiradius 
large, unequal, and without order ; central papillae of the smaller 
faint, in the larger a faint elevated central ridge. Border indistinct ; 
striae 6 in *01 mm. — (PI. I. fig. 17.) 
Habitat . — Moron deposit (Greville !). 
C. megacentrum. Grove, MS. — Diam. -12 to -125 mm. Surface 
somewhat convex. Central space and rosette absent. Markings 
angular, 1J to 3 on the central area, which extends to J or J of 
the radius, beyond this 2J in *01 mm., and increasing gradually 
outwards to about § of radius, thence decreasing to the border ; 
the central papillae prominent; irregular on the central area, 
beyond this in straight rows, with secondary oblique decussating 
