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



f Valve cymbiform , . . . . G. Cymbella Bbun. 



15. ■! — clavate . . ... ... G. siibclavatum Gkun. 



I — lanceolate . . . . . . , .... 16. 



..„ J StriBB radiate . . ... . . . G. eriense Gbun. 



almost transverse G. parvulum KUtz. 



= r 



Astigmatica. 



^ . Axial area narrow or indistinct ... ... . 2. 



— distinct . . . . . .5. 



'I 



M 



Central area distinct ... ... ... . ... 3. 



— — indistinct .... . . G. exiguum !&utz. 



(Valve lanceolate . . . . . G. transsylvanicum Pant. 



— clavate .... . . . . . G. olivaceum Ltngb. 



\ — linear-clavate . . . . G. peruvianum Gbun. 



\ — linear, with broad apex and basis . . . 4. 



. ( Central area rounded . . . . G. Salinarwm Pant. 



' \ — ■ — a transverse fascia . . . . G. cestuarii Cl. 



, ( Axial area narrow, dilated in the middle . G. kamtschaticum Gkun. 



' \ — — broad ... 6. 



{Strise 31 to 22 in 0,0 1 mm. . . . . . G. abbreviatum KtJTZ. 



— 16 to 18 — . . . .... . . G. brasiliense Gbun. 



— 6 in — — . . ... . . G. Puiggarianum Gbun. 



1. G. eriense G-run. (1878). — Y. lanceolate, slightly clavate with rounded, obtuse ends. 

 L. 0,032 to 0,042; B. O.ois to 0,oi4 mm. Axial area narrow, linear; central area small, rounded, 

 with a distinct stigma. Strise radiate, 14 to 16 in 0,oi mm. — Gbun. Casp. Sea Alg. p. 12- 

 V. H. Syn. XXIII f. 10. 



Fresh water: Lake Erie, N. America (Grun.). 



This species in unknown to me, but to judge from the figure, it is not closely allied to any 

 other Gomphonema. 



2. Cr. parvulum KtJTZ. (1844). — V. lanceolate-clavate, with rounded or rostrate to capitate 

 apex, gradually tapering from the middle to the narrow often subcapitate basis. L. 0,o2 to 0,03; 

 B. 0,006 to 0,007 mm. Axial area indistinct; central area indistinct or small and unilateral. 

 Stigma frequently indistinct. Strise 13 to 15 in 0,oi mm., almost transverse, indistinctly punctate. 

 — Sphenella parvulum KtJTZ. Bac. p. 83 PL XXX f. 63. Gomphon. parvulum V. H. Syn. p. 125 

 PL XXV f. 9. G. parv. var. subcapitata V. H. Syn. f. 11. G. parv. var. lanceolata V. H. Syn. 

 f. 10. G. Lagenula V. H. Syn. PL XXV f. 7, 8. 



Fresh water: Sweden! England! Belgium (V. T.), France! Athens! Italy! Sandwich Islands! 

 Tahiti! New Zealand! New Jersey! Dakota! Jamaica! Brazil! Ecuador! 



Var. siibelliptica Cl. — V. elliptic-lanceolate almost symmetrical, with scarcely rostrate 

 apex. L. 0,015; B. 0,oo5 to 0,oo6 mm. Striae 13 to 14 in 0,oi mm. 



Fresh water: Greenland! Falmouth! Tasmania! 



Var. exilis Grun. — V. subclavate, narrow, linear-lanceolate, with rounded, not rostrate 

 apex. L. 0,02 to 0,oo5 mm. Striae 18 to 19 in 0,oi mm. — Grun. Casp. S. Alg. p. 10. 



Fresh water: Rimforsa in Westergotland, Sweden (Grun. ad. icon, in litt). 



Var. exilissima Grun. V. narrow, lanceolate, subclavate, with slightly rostrate ends. L. 0,02; 

 B. 0,005 mm. — Grdn. in V. H. Syn. PL XXV f. 12 (V. H. T. 17). 



Fresh water: England! Ecuador! 



Var. micropus Kutz (1844). — V. slightly clavate, lanceolate, with obtuse apex and subacute 

 basis. L. 0,025 to 0,03; B. 0,oo7 to 0,oo8 mm. Striae 8 to 13 inO,oi mm. Central area unilateral, 

 narrow. — G. micropus KtJTZ Bac. p. 84. V. H. Syn. p. 125 PL XXIV f. 46, XXV f. 4, 5, 6. 



