1888-89.] Mr John Rattray on the Genus Coscinodiscus. 511 
“Barbados” (Johnson! Cleve!); Rappahannock River, Va. 
(Rogers !) ; * Kekko and Sta Maria deposits (Grove !) ; Szent Peter 
deposit (Pantocsek ! Grove !) ; San Benito deposit, California 
(Grove!); Kamtschatka Sea, 1700 fms. (Greville ! Bailey!); 
Atlantic Telegraph soundings (Roper !) ; * Piscataway deposit 
(Greville !) ; Santa Monica deposits (Cleve and Moller ! Firth !) ;* 
King’s Mill (Schmidt) ; Nicobar Islands (Schmidt) ; Mascara 
(Cleve and Moller !) ; Nottingham deposit, Md. (Cleve and Moller!); 
Briinn Tegel (Cleve !) ; Holland’s Cliff (Cleve !) ; anchor ground, 
Laguna Harbour, 20 miles N. of Laguna in the sea (Rahenhorst and 
Schwarz !) ; Marstrand (Kinker !). 
Yar. decussata, nov. — Diam. T15 mm. Markings 3 in '01 mm., 
subequal to the zone at the border, the secondary oblique 
decussating rows obvious ; radial rows not differentiated. Border 
more sharply defined. 
Habitat. — Roundstone Bay, Ireland (O’Meara !). 
Yar. latemarginata. Pant., Fossil. Baeil. Ung ., p. 70, pi. xxii. 
fig. 201. — Diam. *057 mm. Markings subequal, 3 in *01 mm. 
Border sharply defined. Striae more distant. 
Habitat. — Elesd deposit, Hungary (Pantocsek !). 
Yar. intermedia , Rattray. C. robustus , var. intermedia , Grun., 
Denk. Wien. Ah., 1884, p. 72. — Diam. T65 mm. Markings increasing 
slightly outwards, those at the centre somewhat larger than those 
on the adjoining area; near the centre 2, towards the border 1J, at 
the border 3 to 3J in ’01 mm. — G. robustus , Sch. (not Grev.), Atl., 
pi. lxii. fig. 6. 
C. robustus. Grev., Trans .Micr. Soc., Lond., 1866, p. 3, pi. i. 
fig. 8. — Diam. from ’0825 to *325 mm. Surface slightly convex 
towards centre. Central space and rosette absent. Markings 
pearly, 1J to 2 in ’01 mm., suhequal for about § of radius, smaller 
towards the border, at intervals smaller areolae sometimes distinct 
among the larger, the central papillae prominent ; radial rows 
inconspicuous, sometimes secondary, suhconcentric or short oblique 
decussating rows visible. Border prominent, sharply defined, from 
to 2 V °f radius broad ; striae evident, 4 to 6 in '01 mm. — Sch., 
* In the collection of Dr Greville. 
