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



As CymhelJa elegans Cramer has issued in Rabli. Alg. Eur. N:o 1441 (18(33) a sample con- 

 taining several Cymbella>, as C. (Jisiula, C. helvetica, C. delicatula, C. Icevis, C. affinis, ('. lepto- 

 ceras, C amphicfpluda and C. asj)era. As no description or figure of C. elef/ans is given, it is 

 impossible to determine what form the name denotes. 



9. C. Iievis Naeoeli (1849). — V. strongly a.symmetrical, semilanceolate, gradually tapering 

 from the middle to the ends. Dorsal margin arcuate; ventral margin straight or sliglitly convex 

 in the middle. L. 0,02.5 to 0,o3.5; B. 0,oo7 to 0,oo8 mm. Median line somewhat excentric and 

 slightly arcuate. Axial area indistinct. Striae of the dorsal side 13 (middle) to 15 (ends) in 0,oi 

 mm., .slightly radiate. Stri;e of the ventral side Ifi (middle) to 17 (ends) in 0,01 mm. almost pa- 

 rallel and finely punctate. — Naeg. in Kiitz. Sp. Alg. p. 59. V. H. Syn. p. i\2 PI. Ill f. 7- 

 A. S. Atl. IX f. 35. 



Fresh' water: Norway (Dovre)! Sweden (Gellivaara to Ortofta in Skane)! Finland (Lapland 

 to Karelen)! Scotland! Zurich (Grun.), Tours du Tlhone! 



10. tl. pusilla (tRUN. (1875). — V. asymmetrical, narrow, semilanceolate, with subacute ends 

 and arcuate dorsal, straight or slightly convex ventral, margin. L. 0,23 to 0,04; B. 0,00.') to 0,007 f) 

 mm. Median line straight, strongly excentric. Axial ai'ea very narrow, not, oi' slightly, dilated 

 around the central nodule. Striffi 15 to 18 (middle) or 16 to 20 (ends) in 0,oi mm., radiate in 

 the middle, transverse at the ends. — Grun. in A. S. Atl. IX f. 3(3, 37. V. H. Syn. PI. Ill f. 5. 



Brackish water: Sweden (Baltic: Gothland, Malmo)! Halle! Neusiedler See (Grun.), Caspian 

 Sea (Grun.), Normandy! Belgium (V. H.), Bayonne (Atl.), Sardinia (Grun.), Mouth of Jenissey ! 

 South Africa! Ecuador! 



11. ('. yarreiisis A. S. (1881). — V. narrow, semilanceolate, acute. L. 0,o7r. to 0,ii; B. 

 0,012 to 0,0 1.^ mm. Median line nearly central; its terminal fissures in the ends. Axial area 

 narrow, linear, dilated in the middle to an elongated central area. Stria* 11 inO.m mm, somewhat 

 more distant in the middle, where they are radiate, parallel in the ends. — Encyon? yarrense 

 A. S. Atl. LXXI f. 1(3. 



Slightly brackish water: Yarra-Yarra (Australia)! Tasmania! 



12. C rupicola Grun. (1881). — V. slightly a.symmetrical, lanceolate, gradually tapering 

 from the middle to the subacute ends. L. 0,02 7 to 0,034; B. 0,004.^ to 0,00."^ 5 mm. Median line 

 almost central, straight. Axial area narrow, not dilated in the middle. Dorsal strife 12 (middle) 

 to 15 (ends) in 0,oi mm. .slightly radiate. Ventral stria; 1(3 in 0,oi mm. slightly radiate — 

 Grun. in A. S. Atl. LXXI f. 70, 71. 



Fresh water (moist rocks): Arctic America! Scotland (V. H. Types), Salzburg (Atl.). 

 This species is very nearly akin to C. leevis and differs scarcely in anything ext'ept the 

 less asymmetrical valves. 



13. C. Reiuhardtii (tRUN. (1875). — V. slightly asymmetrical, elliptic-lanceolate, with 

 convex dorsal and venti'al margins. Ends obtuse. L. 0,03 to 0,06; B. 0,oo8 to 0,oi4 mm. Median 

 line neaidy central, straight. Axial area narrow, gradually dilated to the middle, where it ex- 

 pands to a moderately large central area. Strice 10 (middle) to 13 or 14 (ends) in 0,oi mm. The 

 median stria", are more distant than the rest and slightly radiate. Towards the ends the striae 

 become almost parallel. — A. S. Atl. IX f. 27. Cl. M. D. N:o 132. 



Fresh water: Norway (Romsdalen)! Steinitz Sea (Atl.), 



The above description is from specimens in Cl. M. I). 132, determined by (tRUNOw as 

 6'. Reinhardiii. 



14. (,'. leptoceros (Ehb. 1843?) Grun. — V. asymmetrical, lanceolate, with slightly gibbous 

 ventral margin and obtuse, sometimes slightly attenuated ends. L. 0,o2 to 0,04; B. 0,oo8 to 0,oi 

 mm. Median line slightly arcuate. Axial area linear, not dilated around the central nodule. 



