236 (NTBIBUTI0N8 PROM I ill. NATIONAL HERBARIUM. 



1). Valve Apparently without raphe, this being ohecured bj the beaded, 

 marginal keel; markings always transversi NrrzscHii u . 



1>. Raphe hidden in lateral winged keel. Si rirblu u 



a. Valve surface undulated in a Beries of transverse depressions and eleva- 

 tions .Sphinctocyatu p 



l» Valve surface not undulated in a Beriee of transverse depressions and eleva- 



a. Valve outline elliptical, ovoid orrarelj long-lanceolate; marked with 



transverse ribs not quite extending i" the center, thus leaving i 

 hyaline median line; valve surface nearly Hat, rarely spirally 

 twisted; keel winged Surirella p 



b. Valve outline nearly circular; ribs or other markings radial; valve 



Buiface saddle-shaped, rarely almost flat; keel not winged. 



Campyloducus p 

 MELOSIRA C. Ag. 



Melon a I \_r Syst. Alg. 8 9. L824. Kutz. Bacill. 18, 52. L844; 8p. Alg. 30. L849; 



Linnaea 8: 70. L833. Ralls, Ann. Mag. Nat. Bist. 12: 346. pi 9. L843. Thws 



Ann. Mag. Nat. Bist. II. 1: H.7. isis. in part. W. Smith, Synop. Brit. Diat. 3: 



54. L856. Pritch. Bist. Enius. ed. 4. 815. pi. 5.f. 6f 65, 71. L861. Rabh. PI. Eur. 



Alg. 1: 7. 37./. 8. L864. Griff. & Benf. Micr. Diet. ed. 4. 194. pi 17. f. 5 6, 15. 



L883. Castr. Rep. Voy. Chall. Bot. 2: 92. />/. 11. f. i :. Ism;. Van Beur. Synop. 



L97. pi. 85 91. L881; Treat. Diat. 138./. 165 168, pi. 18. f. 60S 618, pi. 19 



614 ' S Brun, Diat. Alp. L34. pi. l.f. i 5, 9. L880. 



taUloneUa Bory, Diet. Bist. Nat. 7: L01. L825, not Bory. L823. 

 Gallionella Ehrenb. [nfus. If,.;. L838. De Toni, Syll. Alg. 2: L331. 1894 

 Lysigonium Link: Nees, Bor. PhyB. Berol. I. L820? O'Meara, Proc. Roy. trish 



lead. II. 2: 248. pi. .'<;./. ;. L875. De Toni, Syll. Alg. 2: 1328. 1894. 

 Orthoseira Thwaites, Ann. Ma^. Nat. Bist. II. 1: 167. 1848, in part. W. Smith, 



Synop. Brit. Dun. 2: :>!». L856. 

 Aulacoseira Thwaites, Ann. Mai:. Nat. Bist. II. 1: L67. L848, in part. 

 /'-/ alia Beib. Krit. Overs. Danske Diat. 33. L863, in part. De Toni. Syll. Alg. 2: 



L349. L894. Grun. Denkschr. Akad. Wien 48 J : 93. L884. Cleve, Bih. Sv. Vet. 



Akad. Ha... 11. 1 : 7. L873. 



Two generic names antedate Agardh's Melosira. Tin' first is Lysigonium Link. 

 Ii Beeme that his type Bpeciee was one of the then indefinitely fixed algae called 

 Conferva moniliformis, bul was probably not a diatom. Ai Leasl Ehrenberg so con- 

 tends. Link himself, according to Ehrenberg, abandoned the name in L824. Ii" 

 ii can be unmistakably proved to have been applied in a diatom of this character, 

 Link's name must replace that of Agardh. The Becond name is Gallionella (Gaillo- 

 nella), given by Bory St. Vincent in L823, but without definite outline or the 

 enumeration of any species. Two years later, L825, in the same work Bory does 

 describe two Bpeciee, G. nummuloides ami < i . moniliformis. But in the preceding year, 

 L824, Agardh L r a\«- the generic name Melosira to these diatoms and described five 

 Bpeciee. This name i- therefore valid, unless, as above Btated, Link's Lysigonium 

 can be clearly identified with this genus The genus has been variously divided by 

 different authors. The most important attempt at division, a thing desirable in 

 itself on account of the large number of species in the genus, was carried out by \Y. 

 Smith.'' based on the analysis of Thwaitee. c Smith accept- the division of this 



Ehrenb. [nfus. L66. Lfi 



I' \\ . Smith. Synop. Brit. Dial. 2: 54. 18 ■<• 

 • Ann. Mag. Nat. Bist. II. 1: L67. 1848. 



