Algae of the English Lake District. By Wm. West. j 725 
C. nitidulum De Not. H., Bo., Wythburn, Kirk Fell. 
C. subtumidum Nordst. H. 
C. tumidum Lund. L. 
C. Phaseolus Breb. H., Scawfell, Scarf Gap Pass, Stye Head 
Tarn. 
C. PSEUD ATLANTHOIDEUM Sp. n. Fig. 21. 
C. parvum, lj-plo longius quam latius, profunde con- 
strictum, sinu lineari; semicellulae subtriangulares, angulis 
inferioribus latissime rotundatis, lateribus concavis, apice 
angusto rotund ato ; a vertice visae anguste ellipticae ; mem- 
brana glabra. 
Long. 19-5 fi; lat. 13*5 /x ; lat. istbrn. 4 /x ; crass. 
6*5 fi. L. 
This differs from C. atlanthoideum Delp. in being relatively 
narrower and in its different vertical view. 
C. scenedesmus Delp. B., Bn. 
C. rectangular e Grun. Bt., Hk. 
C. bioculatum Breb. Sk., B., Hk. 
*forma depressa Scbaar. B. 
C. tinctum Ralfs. Frequent. 
*var. intermedium Nordst. 
Long. 14-15 /a; lat. 10-12 /x ; lat. istbm. 6 fx; crass. 
8 / 1 ; Bo. Frequent. 
C. exiguum Arcb. Hk. 
*C. Begnellii Wille (Bidrag til Sydam. Algfl., p. 18, t. i. f. 34). 
Hk., common. 
Long. 11-12 /x ; lat. 11-14 /x ; lat. istbm. 3*5-4 /x ; 
crass. 6 /x. Fig. 20. 
Tbe forms of this varied considerably. Perhaps C. abruptum 
Lund. var. gostyniense Racib. (Nonn. Desm. Polon., p. 24, t. ii. 
f. 13) may be another form of this species. 
C. subcapitulum sp. n. Fig. 29. 
C. parvum, paullo latius quam longius, profunde con- 
strictum, sinu acutangulo aperto ; semicellulae elliptico- 
angulares ; latera inferiora et superiora recta angulum sub- 
rectangularem formantia ; apicibus truncatis et subretusis ; 
a vertice visae ellipticae polis acutis; a latere visae rotundo- 
ellipticae ; membrana laevis. 
Long. 17 fx ; lat. 19 fx; lat. istbm. 4 fx ; crass. 7*5 /x. 
Bn. 
This differs from C. capitulum Roy et Biss. (Jap. Desm. in 
Journ. Bot., 1886, vol. 25, p. 195, t. 268, f. 9) in tbe truncate 
subretuse ends, tbe acute angles of the semicells, in tbe non-acuminate 
sinus, and in tbe subacute poles of tbe vertical view. 
