72 P. T. CLEVE, SYNOPSIS f)F THE NAAMCUI/iII) DIATOMS. 



To this geiivis probably belongs Stauroneis decora Grev. (T. Bot. Soc. of Edinb. Vol. VIH 

 p. 23() Pl. IIT f. 11) from New Caledoiiia. It is very transparent, lanceolate, in lengtli 0,i-i nini. 

 and lias a sliort stanros not reaching the longitndinal ridges. 



Scoliotropis Cl. N. G. 



Valve elongated .symmetrical. Median line sliglitly sigmoid, especially towards the ends. 

 On both sides of the median line is a longitndinal line. Structnre donble: coarser transverse costcb 

 and finer pnncta, disposed in obliqnely decnssating rows. Connecting zone witb longitndinal rows 

 of sliort stricB. 



This genus has been formed for Scolioplcura latestriata CtRUN. as this form is entirely 

 diiferent from the trne Scolioplenra-forms in its structnre, which is the same as in (.iomphoneis, 

 and in tlie complex natnre of its connecting zone. Låter on another, very interesting species, 

 Avas diseovered, nnfortnnately not yet fonaid in entire specimens, S. GiUesii. 



The frnstnles of S. latestriata hava along the connecting zone 

 on each side, Uvo chromatophore-plates, the margins of which are 

 gently nndnlating. In front-view tlie plates have a sinns aronnd 

 the central plasma-mass. 



1. S. latestriata Bréb. (1849). — V. linear, narrowed at the 

 cuneate ends. L. O, i to O, is; B. 0, 02. 5 mm. Median line strongly 

 sigmoid. Structnre: strong costa;, 7 in 0,ui mm., transverse. trongli- 

 ont, and minute pnncta, 18 in 0, 01 mm., forming oblif[ueh' de- 

 cnssating lines and alternatiug in donble rows with the costis. 

 Connecting zone with several longitndinal rows of short striae. about 

 25 in 0,01 mm. — Ampliipr. latestr. Bréb. in Iviitz. .Sp. Alg. p. 93. 

 Navic. coiwexa W. Sm. B. D. I p. 49 Pl. XVI f. 13(5 (1853). Scolio- 

 pleura latestriata V. H. Syn. p. 111 Pl. XVII f. 12. 



Mariiie: North Sea (Sweden! England! Belgium!), Caspian Sea 

 (Grun.). Atlantic coasts of North America! West Indies! California! 

 Var. Amphora Cl. (1892). — V. asymmetrical, witli a more 

 convex dorsal side. Median line curved, with the terminations 

 directed towards the .same .side. — Scoliotr. latestr. rar. Ampliora Cl. Diatomiste I p. 78 Pl. 

 XII f. 13. 



Marine: Long Island Sound, New York! 



I have only seen detaclied valves, of this variety, so I do not know whether lioth valves 

 have the median lines on the same side of the frnstnle or not. 



2. S. Gilliesii Cl. a. Comber N. Sp. — V. convex, linear, tapering at tlie soinewliat roundcd 

 ends. L. 0,2; B. 0,oo mm. Median line straight (sigmoid at the ends?). Central nodule small; its 

 median poi'es turned in opposite directions. Axial and central areas indistinct. CostiE 7 in 0,i)i mm. 

 a little closer towards the ends, parallel, somewhat com-ergent at the ends, crossed by a longi- 

 tndinal keel, enclosing a fnrrow broader than a half of the breadth of the valve. Tlie costa; 

 alternate with donble rows of pnncta, about 14 in (),ui mm., forming loiigitudiiial iiiidulating rows. 

 — Pl. I f. 16. 



Marine: Jamaica (Comber CoU.)! 



This species, named in lionour of Captain Gillies, wlio procured the material, is a very 

 characteristic, large form, of which fragments only have been fonnd. The median line seems to be 

 curved, probably in contrary directions, at the ends. The median pores have the same charac- 



8. latcstriafa, 500 times magnified. 



