1888 - 89 .] Mr John Rattray on the Genus Coscinodiscus. 605 
apedicellahis, Rattray, and abnormal valves of A. Kittoni. They 
are also sometimes absent (hence inconstant) in otherwise normal 
valves of A. formosus and A. excavatus. Tor these reasons the 
species seems to me to have more claim to rank with Aulacodiscus 
than with Greville’s later genus Cosmiodiscus. 
C. vulgaris. Schum., Schrift. Plugs. Oek. Ges. Konigsb., 1867, 
p. 62, pi. iii. figs. 74 a-c. — Surface moderately convex. Centre 
mostly with markings similar, sometimes larger than the others, 
more rarely without markings. Markings equal, angular, about 
7J in -01 mm. 
Schumann explains that, with the object glass raised, the markings 
appear round, when depressed angular and resolved into 4 smaller 
markings. To this he joins C. radiatus, Ehrb. ( Mikrog ., pi. xxxv. A. 
17. fig. 6); C. perforatus, Ehrb. [Mikrog., pi. xviii. fig. 46); C. 
intermedius , Ehrb. [Mikrog., pi. xxxiii. 13. fig. 3); and C. radiolatus, 
Ehrb. [Mikrog., pi. xxxix. 2. fig. 18). The species is insufficiently 
diagnosed, and by the union of the above-named species of Ehren- 
berg it becomes too extensive. It may be abandoned, being pro- 
bably identical with C. radiosus, Grun. 
Specimens were observed by Schumann from the Baltic. 
C. intermedins , Ehrb., Mikrog., pi. xxxiii. 13. fig. 3. — Diam.? 
Central space and rosette absent. Markings increasing gradually 
from centre outwards ; rows radial, non-fasciculate. 
This species found in San Francisco tripoli cannot be determined 
with certainty. The markings are similar to those of C. argus, 
Ehrb. [Mikrog., pi. xxi. fig. 2), though smaller. C. radiolatus 
Ehrb. [Mikrog., pi. xxxix. 2. fig. 18) is identical, but distinct from 
G. radiolatus [Mikrog., pi. xxii. fig. 4), which recalls C. radiatus, 
var. subcequalis, Grun. 
C. radiolatus. Ehrb., Abh. Per. Ak., 1841, p. 412, pi. i. 3. fig. 19; 
pi. ii. 6. fig. 16. — Markings small, equal, 9 in *01 mm.; rows radial. 
The specimens figured by Ehrenberg [Mikrog., pi. xviii. fig. 36 ; 
pi. xxii. fig. 4; pi. xxxix. 2. fig. 18), from Peru, Cuba, and Rich- 
mond, Ya, disagree to a considerable extent, and may not repre- 
sent the same species. Ralfs distinguished C. radiolatus from C. 
ajpollinis by the absence of a central space. Janisch, on the other 
hand [Abli. Schl. Ges. voter. Cult., 1862, Heft ii. p. 4; pi. ii. b, 
fig. 17), describes the markings as strong, round, and decreasing 
