120 p. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



and oblique strut almost equidistant, 1!) to 20 in 0,oi mm. — Plenr. rectum Donk. T. M. S. VI 

 p. 23 PI. Ill f. 6. Amj)hiprora Ralfsii Arnott M. J. VI p. 91 (1858) ad spec, authentica. Donlinia 

 recta V. H. Syn. p. 119 PI. XVII f. 9. Per. IX f. 4. P. Loren.zii Grun. Verb. 18()0 p. 558 

 PI. VI f. 4. Per. Yll f. 17. 



Marine: Xortb Sea! Mediterranean Sea! Adriatic! Labuan! ("liina! Port Jackson! Florida! 



A^ar. inteniicdia Per. (1891). — V. more lanceolate, witb less asymmetrical ends. — Donkinia 

 recta var. int. Per. p. 30 PI. IX f. 7, 8. 



j\Iarine: Cherbourg (Per.), Firth of Tay! 



Var. Thumii Cl. (1891). — L. 0,i to 0,i3; B. 0,oii to 0,oi2 mm. T.S. : L.S. '■!•-„,. ^^ .,«,-' ,7 

 in 0,01 mm. — IhnMnia Thumii Per. p. 30 PI. VII f. 28, IX f. 10. 



Marine: Balearic Islands! Seychelles! Sumatra! 



Var. tiiivuta Donk. (185«). — Smaller. L. 0,00; B. 0,oi2 mm. Striie 19 in 0,oi mm. — 

 Fleur. minutmn Donk. T. M. S. VI p. 24, PI. Ill f. 8. Donlima niin. Ralfs in Pritch. Inf. p. 921 

 (1861). Per. IX f. 9. 



Marine: Newcastle! Firth of Tay! 



27. 0. liiieare Grun. (1880). — V. narrow, linear, almost straight, unilaterally narrowed 

 towards the ends. L. 0,17 to 0,26; B. 0,oi to OjOi.") mm. Median line sigmoid, strongly excentric. 

 T.S. : L.S. -^riv "V26 i" ''''^i "^"^- — Rhoic. lincare Grun. A. D. p. 59. Per. IX f. 11 (median line 

 incorrectly rejiresented as central). 



Marine: Adriatic! Seychelles (Grun.), Port Jackson! Colon! 



Var. louf/issima ('l. (1881). — V. very narrow, with obliquely rounded ends. L. 0,10 to 

 0,17; B. 0,007 mm. T.S. : L.S. 'V.,,, •-•7„., in O.oi mm. — Flntr. (J)n,d:?) litmi. V,l. X. R. I), p. C 

 PI. I. f. 8. Per. VII f. 16. 



Marine: Mediterranean Sea (Gulf of Naples, Balearic Islands)! 



28. Gr. ailgustum Donk. (1858). — V. very convex, thin, linear, with unilaterally attenuate, 

 acute ends. L. 0,i26 to 0,14; B. 0,oi5 mm. Median line diagonal in the middle and then marginal. 

 T.S. : L.S. 2«/2.. in 0,oi mm. — Pleur. angmttm Donk. T. M. S. VI p. 24 PI. Ill f. 9. Dovhinia 

 angnsta Ralfs "in Pritch. Inf. p. 921 (1861). Per. IX f. 3. 



Marine: England (Donk.), Balearic Islands! 



Var. sumatrana Cl. — Less convex. L. 0,14; B. 0,018 mm. T.S. : L.S. •^/.^^ in 0,01 mm. 

 Median line less excentric. 



Marine: Sumatra (Deby Coll.)! 



29. P. (Rhoicos.) comp.actiiiu Grev. (1857). — Frustule arcuate, with dissimilar valves. 

 V. short, linear, unilaterally attenuated to the obliquely rounded ends. L. (),((8'j to 0,4; B. 0,o\^y to 

 0,05 mm. Upper valve with straight diagonal, median line T.S. : L.S. ^V,,' '''/iS' '%i' "Ao ^" *^''" "i"^- 

 Lower valve with .strongly excentric and sigmoid median line. T.S. : L.S. 'V221 'V191 "/22' 'V22' 

 '%:!' 'V24 "^ ^'0 1 ^^nm. — Loivcr valve: Fleur. comp. Grev. M. J. V. p. 12 PI. Ill f. 9. Donlinia 

 comp. Ralfs in Pritch. Inf. p. 921 (1861). Ehoir. cowjt. Grun. M. M. .7 1877 p. 182. Per. 

 p. 33 PI. X f. 7, 8. lihoic. oceanicuni Per. 1. c. f. 5, 12, 15. BJioic. corsicaiium Per. 1. c. Rlioic. 

 Antillariim Cl. West. Ind. D. p. 9 PI. II f. 14. Flenr. Smithianum Castr. Voyage Challenger D. 

 p. 38 PI. XXVIII f. 6? DonVniia antiqua Grove and Sturt J. Queck. M. Cl. Ill [2J p. 133 (1887)? 

 — Upper valve: Rhoic. Reichardfianum Grun. Hedwigia VI p. 11 (1867). M. M. J. 1877 p. 181 

 PI. CXCV f. 19. Rhoic. compactum Per. p. 33 PI. X f. 6, 8, 10, 13. 



Marine: La Rochelle (Petit Coll.)! Mediterranean Sea! Adriatic! Red Sea! Sumatra! Philip- 

 pines! Port Jackson! Samoa! Tahiti! Galapagos Islands! Honduras (Grun.), West Indies! 



Var. con.'itrieta Grun. (1877). — V. slightly constricted in the middle, with subcuneate ends. 

 L. 0,1. t; B. 0,02 mm. TS. : L.S. '7,9, 'V.,o in 0,oi mm. — Rhoic. {Reichardtii var.?) constr. Grun. 

 M. M. .). 1877 p. 181. 



Marine: Honduras (Grun.)! Adriatic (Grun.)! 



