32S COXlTJBrTlONS from TilK XATIOXAL TIKRCAETUM. 



margliLs; upprr val\r with a broad, ccntjul, liUiyiludirral, hyaliiu' area, sliglitly wider 

 near llir chmHc r of Ihe valve; stri^U' of eoarwe and distanl beads, 1wt> to four on each 

 side of the median \\n{\ trausY(Tse until neor llu' endt^, then l>eeoniing coneentrie 

 to the pointy of the apiees. 



Longlli of valve, 0.08 mm.; wichh of valve^ O.OIS mm. Rows of I'eadiiif^^ nn uiuhT 



valve, SS in OJ nuu.; on ujtper valve, 5G in 0/1 mm. 



Type in the U. S. National Museum, No. 500143, from station 3r;;]oIL Herini^^ Ren, 

 Angns(.21, 1895; 141 fathoms, bottom of gray sand. 



The nearest approaeh to th<^ above is Achnanfhidunn (=Acfnia7}fhrs) aretirfvnf, <4<n"e/' 

 but tlie differences are gr(*atei- Ihan the r(\s(Mnl.>hince. The l>eading on the under 

 (ventral) side of Cleve\s speeii-s is GS in 0.1 mm. with a valval h^ngth of 0.018 mm., 

 whereas in muie it is 88 in O.i jum. with a valval length of 0.08 mm.; hi other words, 

 it is very much finer on a valve about twiee as large, as tlu' j)roportion l>e1 ween sizi* of 

 valve an<1 striation in (M<'ve's spceies Avould l)e in my specimen 4 1 instead of 88 in 0.1 

 mm. But Avhat shows that tliis is not a \ovy finely marked ihougli large specimeti of 

 (lie abov(> is that tlie valves do not taper, but liavt^ blunt, rounde<l ends; the markings 

 are strictly transverse except toward the apices; the stauros is quite broad; the raphe 

 is beaded and bifuicates near the ends; theri' is a broad, hvalinc line on (4ther si(h^ of 

 the raplie; a di^flinctly marked )im of uniform 1)nnidth runs around the entire valve. 



COCCONEIS Ehrenb. 



Cocamds Khrenb. Infus. VXl. pL l-Uf. S-9. pL .?/./. n, hS.SS. 



ra/?/yjy^o/^M'i' Grun. \'erh. Zooh I'ot. (Jes. \Vien 12: 429, 1SGl\ Fenzl. Keise Novaia 



liot. 1: 10. 1S70. 

 Otihonris Uruu. in part, in I'eiizh Reise Xovara l>ot. 1: 9 10. JSJO. 

 Anorfhofuis (]vuu. in Fenzl, Reise Xovara l^ot. 1: 9 10. 1870. 



Gruiiow l)reaks up Khreiiberg's genus by emending its scope and creating the above 

 three new uenera. I <lo n()t find anv advantage in this arramrement. Ehrenbenr's 

 generic concept is a well-marked and prer-ise one; its meml>ers are in clear con- 

 trast with other diatoms by tlieir stiliiary growth attached by the inferior, raj^he- 

 bearing vah e. by the concavo-( onvex >h;ii)e (if the frustules, by the general, perhaps 

 universal, <lissimilarity of the inferior and su}>erior vahes. and by their uniform o^'a! 

 or suljoval contour. IIowe\er useful Orunow's distinctions may be for sul)generic 

 division, it seems to me best to lea\e these forms in the c()mi)a<t and satisfactorv uenus 

 that Kliroid)erg constructe(i for them. Tins \ iew seems to ])revail with most authors, 



Cocconeisa antiqua Teiu]). &. iinni. Mem. Soc. Phys. et Hist. Xat. Gene\a 30'^ 32. 



pi S.f. 5. h=^89. Schnudt, Atlas pL 19Lf. :/), d2. 1877. 

 Cocconris tnulnjiiva Pant. Heitr. r>aci]l. I'ng. 3: pJ. -^J. /. fh'<2. 180;). 



The form from station .'](j0ill is identical with Schmitlt's fi<j:ures al)ove. It is, how- 

 ever, wdde of the tyi>e. and I assign this n;;me to it Avilh some doubt. More tyj)ical 

 specimens occur at station 402911, together with a variety which lacks ihe curved 

 hyaline bands midway between the raphe and the sides. 



Found at stations :U]01IL 4029H, Rering Sea. 



Cocconeis baldjikiana t'irun,; Xan lleur. type no. 540. Schmidt. AUas pi. 190. 

 f. 7-10, h^91. 

 Coccoui i^ si'iiidliun Fdn-enb. ; GruTi. Put. Centralbhitt 33: ;^24. 18S8. (4e\'e in 

 Schmidt. Alias yj/. ;.W./. 7 10. 1877. 



I agree with Schmi<lt in the above citation that Grunow's union of this beaulifid 

 and \igorous f(»rm witli (\ scKtrUmn Fhrenl), is inadvlsa)>h\ Even Suiith's too 

 stronglv nuirked figure f^ of ihe latter lacks the beautiful brtjudening of the markin":s 



uRih. Sv. Vet. Akad. Uamll. 1^^: 25. pJ. -If. ,t.i. hS78. 

 6W. Smitli. Synop. Prit. Diat. 2: pi, S.f. 3-1 185C. 



