42 P. T. fLEVE, SYNOPSIS OF THE NAVIOULOIl) ])IATOMS. 



29. P. Bniiiii Cl. (1891). — V. linear, strongly sigmoid, sudderily attenixated to the acute 

 ends. L. 0,42 to 0,4.'); B. O, si to 0,o33 mm. Median line central. Central nodule small. Ti^ans- 

 and obliqne strite '^732 ^^ 0,oi mm. — Per. p. IG Pl. VI f. 8. 



Marine (pelagic): Bay of Bengal! Java! 



30. P. Javanicinn Grun. (I87.S). — V. narrow, lanceolate, gently sigmoid, aeute. L. 0,125 

 to 0,144; B. 0,019 to 0,022 mm. Median line nearly central in the raiddle, excentric toward.s the 

 ends. Transv. and obl. strife eqnidistant, abont 28 in 0,oi mm. — F. aiif/uhifuni var. jar. (iRrx. 

 in Cl. M. D. 145. R javanicum Grun. A. D. p. ^>2 (1880). Per. V f. K). 



Marine (pelagic): Java! China! 



This species bas the outline of P. sfrif/osnni, but i,s thinner (dry, yellowish) and more aente. 

 It is most nearly akin to F. cicutnm. As F. liyaliiium, Grunow desttribes in A. I), (p. ö2) a similar, 

 pelagic foi'm from Triest (L. 0,08.'); B. 0, 01 dö mra.), the striation of which is too delicate for measuring. 



31. P. iicntum Norm. (18fil). — V. lanceolate, gently sigmoid, acute. L. 0,24 to 0,.i; B. 

 0,(12 to 0,028 mm. Median line sigmoid, very excentric towards the ends. Transv. and obl. stiite 

 -■^/.,j, -7i9, ^■'/■•n ™^ *^'>oi mm. — NoRM. Pritch. Inf. p. 920. Per. Ill f. 1, 4. F. acufuiii var. ati.sfral- 

 as'mm Grun" in Cl. M. D. 286 (1882). 



Marine (pelagic): Enrope (Norm.), Croisic (Per.), Java (Deby Coll.)! St Vincent, An.stralia! 

 Yeddo Bay (Brun Coll.)! 



This species is nearly akin to F. javaiiiciti)/ and F. Stuxbergii, from which latter it differ.s 

 by its less acute oblique stritt and the excentricity of its median line towards the ends. The fig. 2 

 in PERA(iALLo's mouograph bas the outline and median line of F. Sfuxhergii, Init the .striation of 

 F. (icitHiiii. The tig. o in the same monograph is another, allied form, described here as F. prla(i'tcuni 

 Per. and formerly mistaken by me for F. ciciifiiiii var. australasicum Grux., wliicb latter now seenis 

 to me to be identical with F. acutuni. 



32. P. (Hlioicosigma?) niaroccanum Cl. (1891). — V. narrow. lanceolate, gently sigmoid, 

 gradually attenuated to the acute ends. L. 0,2 to 0,3; B. 0,02 to 0,0:17 mm. Median line sorae- 

 what excentric, sigmoid. Transv. and obl. striie "/is' '"Aq i'^ "''" ^^^'"- Angle abont 70". — FJioico- 

 sigma viarocc. Per. p. 32 Pl. IX f. 22. 



Marine; Marocco! Gulf of Naples! 



This form is doubtful as a species and rec[uires further examination. 



33. P. iestuarii Bréb. (1849). — V. lanceolate, gently sigmoid, witli slightly rostrate ends. 

 L. 0,07 to 0,08; B. 0,017 mm. Median line more sigmoid than the valve, excentric. Transv. and 

 obl. striaj equidistant, 19 to 21 in 0,oi mm. — Nacic. (est. Kutz. Sp. Alg. p. 890. P. cest. "\V. S.m. 

 B. D. I p. 65 Pl. XXXI f. 275. Grun. A. D. p. 52. Per. p. 12 Pl. V f. 11 to 13. P. candidmi, 

 ScHUM. Preuss. 1). II Nachtr. Pl. II f. 57 (1867). F. anquJafuni rar. cest. V. H. Svn. p. 115 

 Pl. XVIII f. 8. 



Marine: Noi'th Sea! Adriatic (Grun.), Caspian Sea (Grun.), California! 



This species bas the striation of F. tnigulafmi/ but, by the dexure of tlie median line, seems 

 to be nearer akin to F. lanceolafum. 



34. P. latiim Cl. (1880). — V. rhomboid-lanceolate, slightly sigmoid, gradually tapering to 

 the subobtiise ends. L. 0, 074 to O, os.'); B. 0,02 mm. Median line slightl}- sigmoid, excentric towards 

 the ends. Transv. and obl. stria.' '-7.., in (^oi mm. — Cl. A. D. p. 14, 51 1'1. III f. 68. 



Marine: Finmark! California! 



This form requires a closer examination. 



35. P. rlionibeiim Grun. (1880). — V. rhomboidal, sigmoid, often angular in the middle, 

 and with olituse ends. Ij. 0, 12 to 0,2 6; B. 0,o.t to O, o 7 mm. Median line strongly sigmoid towards 



