2()0 CO:^TR1BUT10XS FEOM THE NATJONAL irERBAElUM. 



Coscinodiscus woodwardii Eulcn. Dial. Sp. Typ. no. IKi, 18(18. Schmidt, Atlas 



pi 60, f. S, pi. HI, f. -?. 1878; pi. 6r>.f. 2. 1881. 



I do not fmd f^atiafartory nnison for plaf'ing this (!iatoin undfr C. apioflatjis l-'lironl), 

 as is done by Pvattray^ and copiod hi Dc Toni,'^ Althou<;h our huowledge of (ho latter 

 Lspccicri is inotit obscnr(', yol ^o far as tin* form is now rcprcisoutod iL lias only a romuLu 

 ros<*nihlance to the ahovo. Its typical structuri! is with beaded valves, whil(^ tin; 

 abov(^ is covered wilh a fiiie n(^tw(trlv; and altliough Ihe transition from beads to h(^xa- 

 gons l)y the enlargement oi llu^ Ix^ading and 1heir suhso(]nent lateral prc^ssnre is an 

 easily understood one, I think the form is then so far from the type as to have passed 

 over into another species. Tlattray has, T thinhj suggested a more important afhnily 

 than Ihe one above l>y his remark^" tliat (\ apiculatus '*when its markings are jDolygonal 

 and in contact is disf inguished from (7. radial. i,^ Ehn^nl). by tlie presence of a central 

 sjnice." This is very nearly the structun^ reprosented hy C, tcooJuard'tl^ which I 

 AVouhl therefore prefer lo phico as a variety of (\ radlalm rather than to unite it 

 with C, aplcidatiiSj as I look upon lh<^ jninute and irreguhu' crniral area of this si)ecies 

 as less signiiicant than tln^ strikiTig structural cordrast bc^tweon it and C. apirulalus. 

 \\\\\ for the present at hnisl it is Ix^tter to keep this species independent, as is done by 



Grunow, Sclimidt, and oth(TS. Hat)irshaw makes tliis name synonymous with C. argiis 

 Elirenb., an identificat ioji ipiite (tut of the question. 

 Eound at station 209111, off ( alifoniia. 



ACTINOCYCLUS Ehrenb. 



Actinocyclus Ehrenl>. tier. Akad, Wiss. 15erl. 1837: (ih ISMS; Infus. 171. I8;?8; Ber. 



Akad. Wiss, Berl. 1840: 202-204. 184E 

 Pyxidinda EVircmb. in part ; Rer. Akad. Wiss. BerE 1844: 85. 1845* 

 EifpodiscHs lOhrenb. in part; W. Smith, Synop. BriE "Dial. 1: 24. pL 4*/- 4L 185:h 



Breb. Journ. Qu<4c. Micr. Club 2: 71. 1870. Gn^g. Trans. Eoy. ^oc. Edinb. 21: 



50E1857. 

 Adlnoptychas Ehrenb. in part; Ehrenb. Mikrog, j)L JS.J\ J2. 1854. Kiitz. Bacill. 

 ■ 134. 1844. Bright. Quart. Journ. Micr. Sci. 8; 94. 18(i0. 

 Aaliscus Ehrenb. in part; Babli. Fl. Eur. Alg. 1: 820. 18G4. 

 Ilyalodlscus Ehrenb. in jtart; IT. L. Smith, Amer. Journ. Mi<-r. 2: 100. 1877. 

 Slicfodisciis Grey, in 'p'Civt] Grun.; Van Heur. Synop. pL 118, f. ■?. 1881. 



PfxAmrrt Ehrenb. in part; Grun.; Van Heur. Synop. p/. llS.f. 5. 1881. 



}ficropodiscus Grun,; Van TI(nir. Synop. pJ. US^f, 5, 1881. 



iiopt^na Grun.; Grun in Van TIeur. Synop. pi, IIS,/, 6". note. 1881. Ratt. Journ. 



Roy. Micr. Soc. 8-: 017. 1888. 

 Co^v*mo<:fisc(is Elirenb. in part; Grun. Deidvschr. Akad. Wicn 48^: 83. 1884. Norm. 



Trans. Micr. Soc. Lcmd. n. s. 9: 7. ISGl. Grove, Proc. Hoy. Soc. Edinb. 17: 410. 



1890. 



This genus is one of extreme (HfFiculty — first, because of \ho remarkable confusion 

 bol.ween it and other genera, especially in llu* <*arli<T writers; the result boing that 

 such actinocycloid forms as are treated by them arc diihcult to find. Thi? is especially 

 the case in regard to this genus and Actinoptychus Ehrenb., on tlie part of Ehrenbcrg, 

 Kiitzingj Greville, Brightwell, and others, a condition gi-owing out of the fact that 

 when Ehrcnberg first constituted the genus Actinocyclus it made no distinction 

 between these and tln^ Actinoptychus forms, which, though so dissimilar^ were not 

 separated until 18 10, avIicu Ehrenberg created the genus Adinoptychus for that pur- 



"Eroc. Roy. Soc. Edinl). 16: 571. 18S0. 

 &De Toni, Syll. Alg. 2: 1283. 1894. 

 cOp. cit. 570. 



