510 
Proceedings of Royal Society of Edinburgh. [sess. 
Mikrog pi. xx. figs. 29a, b; Sch., Atl., pi. lxv. fig. 7;* Raben., Alg. 
Europ., Nos. 2484, 2485 ; 0. radicdus f. heterostida, Gran, in Pant., 
Fossil. Bacil. TJng ., p. 70, pi. xx. fig. 184; C. oculus-iridis, Sch. in 
Atl., pi. cxiii. fig. 2 ; 0. subconcavus forma major , Sch., Atl., pi. lxii. 
fig. 7 ;f (excl. C. limbatus, Jan. et Raben. — Raben., Beitr. Kennt. u. 
Verbreit. Alg., Leipz., 1863, p. 7, pi. iv. fig. 1; and C. marginatus, 
Kiitz., Bacil., p. 131, pi. i. fig. 7), 
Hardman’s original Monterey specimen, on which C. robustus, 
Grev., was founded, is not in the Grevillean Collection of the 
British Museum, but two specimens on a slide of Bermuda tripoli, 
labelled by Greville “ C. robustus ,” and now in this collection, belong 
to C. marginatus. The C. limbatus, Jan. et Raben., has a central 
space, markings increasing to about the semiradius, and again 
decreasing to the border. Forms occur in Cambridge deposit, 
Barbados, similar to that figured by Schmidt (Atl., pi. lxv. fig. 7). 
Stokes has labelled specimens of this species C. ambiguus. 
Schmidt is only prohibited from uniting the specimens figured on 
pi. lxii. figs. 11, 12, with C. velatus by the small size of the mark- 
ings and the absence of the fine puncta which, according to Grunow, 
cover the surface of that species. 
Habitat. — Richmond, Va.; tripoli from Columbia River Oregon, 
Patagonian tufa ; plastic clay, Aegina (Ehrenberg, Schmidt); Notting- 
ham, U.S. (Hardman oa San Diego, San Pedro (H. L. Smith !) ; 
Bajtha, Elesd Also-, Felso-Esztergally, Kekko, Mogyorod, Szakal, 
and Dolje deposits (Pantocseck !); sounding from 2950 fms., H.M.S. 
Challenger (Rae !) ; “California” (Deby ! Cleve!); Cambridge de- 
posit, Barbados (Hardman !) ;t Monterey (Stokes ! § Firth ! Greville ! 
Cleve !) ; Sta Barbara deposit (Kinker !) ; Moron deposit (Kinker !); 
Faeroe Channel (Grove !) ; Nagy-Kurtos deposit, Hungary (Rae ! 
Deby !) ; Nancoori (Hardman !) ; soundings off Kurile Islands, 1329 
fms. (H. L. Smith!); Behring Sea, 1681 fms. (H. L. Smith!); 
Los Angelos (Hardman ! Cambridge !) ; || Oamaru deposit (Grove !) ; 
* Quoted “ 0. fimbriatus , Sch. {nee. Ehrb.)” by Grunow, ibid., p. 72. 
t Grunow ( DenTc . Wien. AJc., 1864, p. 72) refers to this simply as C. 
subconcavus , Grun., and proposes to name it C. marginatus, var. subconcava, 
or better, to unite it to C. robustus , Grev., the markings towards the centre 
being 2, towards the border 3 to 3| in ‘01 mm. The central papillae are 
prominent, as in C. robustus. 
4 In the collection of Julien Deby. § In the collection of E. O’Meara. 
|| In the collection of Dr Griffin. 
