"J.") 1 CONTRIBUTIONS FROM nil NATIONAL HERBARIUM. 



I have here figured a form common in several dredgings, which, according to ; 

 cut interpretations, passes under the above name. I do this in order to illustrate .1 

 confusion in the taxonomy "i" this species thai should receive attention Anyone who 

 will compare Greville's original figure of C. robustua with the original figure of 

 Ehrenberg's ( '. marginatua h will see little resemblance between them. Y«i < rrunow, 

 Schmidt, Pantocsek, Rattray, and others give no satisfactory marks of distinction, 

 and we have all sorts of discordant opinions connected with most <>i the modern 

 figures, (irun-iu gives us, on the one hand, a C. robustus intermedia Grun.< which 

 Rattray makes C. marginatus intermedia Ratt.,d and on the other hand Grunow 

 gives a C. marginatus submarginata Grun./ which Rattra} puts under C. robustus 



Grev.< Rattray further states that though th iginal slide of Greville's C. robuttut 



is not available, two slides marked by him (Greville) "C robustut ' w<<\\ in the British 

 Museum are C. marginatus Ehrenb. In view of the foregoing facts I offer the - 

 tion that some one "who has access to the material Bifl oul these forms, and. ii i 

 Bary, drop Greville's Bpecies entirely in favor of Ehrenberg's. The name C. mar- 

 ginatus might Decessarily be retained, instead of the earlier C. limbatus, because of 

 the uncertainty of the two figures Ehrenberg gives for that species ' Under present 

 conditions do such thing as a positive identification is possible. I have labeled some 

 specimens that show a narrow border and an absence of radial arrangement, with 

 obscure or broad papillae in the hexagons, C. robustus Grev., and others, with broad 

 and massive borders, somewhat radial and slightly diminishing areolation showing 

 pronounced papillae, C. marginatus Ehrenb.; hut though the best possible under the 

 present circumstances, those can uot be looked upon as critical identifications. 



Diameter of valve here figured, 0. 17f> mm. 



Found at stations 336] 11. 3712H, off Panama and Okhotsk Sea. 



Coscinodiscus nitidulus Grun.; Schmidt. Atlas pi. 58. f. .'<> 21. L878 (not pi. ItS.f. 

 is. L888). Van Hour. Synop. />l. 182. f. .'. L881. Pant. Beitr. Bacill. [Jng. 1: 

 73. pi. /;../". .'/;. L886. Ratt. Proc. Roy. Soc. Edinb. 16: 180 L889. De Toni, 

 Syll. Alg. 2: L222. L894. Jan. Dial. Gaz. Exped. pi. 5,/. 13. 

 Pound at station L516H, oft' Lower California. 



Coscinodiscus nitidus Greg. Trans. Roy. Soc. Edinb. 21: 499. pi. l!>. f. .',:>. 1856. 

 Schmidt. Atlas />!. 58-. ./". 16 19. L878; Jahresb. Komm. Dent. Meere 2: 94. />/. 3. 

 /'. 32. L874. Pritch. Hist. Enfus. ed. 4. 831. pi. 8.J. is. L861. .Ian. Diat. (la/.. 

 Exped. pl.5.f. 12, 14 16 (not /. 18). Pant. Beitr. Bacill. Ung. 1: 7."). />/. is. 

 f. 166. Van Heur. Synop. Suppl. pi. C. J. ', I . L885. Wolle, Dial. X. A. />/. 94. 

 i. :: 23. L890. Kan. Proc. Roy. So,-. Edinb. 16: 178. pi. I./. 21. 1889? Do 

 Toni. Syll. Alg. 2: Yn\. Cleve A: Moll, type no. L50, IV.. 208, 210, 257, 311. 

 Coscinodiscus for aminosus Grev. Ms. in Coll. Brit. Mus. 



This and the former species show considerable resemblance to certain members of 

 the genus Stictodiscus.0 

 Found at Btation 2807, Galapagos Island-. 



"Tran-. Mier. Soc. Loud. n. B . 14: /;/. /./. 8. L866. 

 6 Ehrenb. Mikrog. pi. is./. ,». 1854. 

 i Denkschr. Akad. Wien 48 J : 72. L884. 

 dProc. Roy. Soc. Edinb. 16: 51 1. L889. 

 - Op. ,n 512. 



/ Ehrenb. Mikrog. />!. 20. f. 29a h. L854. 



'/(f. Schmidt, Alias P l. 202. ./'. ;. L896 and Journ.Quek. Micr. Club II. 3: pi. 5. 

 /'. 7, i- 



