BRITISH DESMIDIE.E. 211 



19. M. Baileyi ; frond granulated ; segments three-lobed ; lobes 



bipartite, end one much-exserted. 



Micrasterias, n, sp., Bailey, in lit. cwnicone (1846). 

 West Point, New York ; and Rhode Island, Bailey. 



Micrasterias Baileyi is allied to M. furcata and M. Crux-Melitensis ; the 

 frond however is minutely granulate, the segments are only three-lobed, and 

 the end lobe is more exserted than it is in those species. The basal lobes are 

 deeply bipartite, the end one merely sinuated. All the subdivisions are bi- 

 dentate at the apex. 



Tab. XXXV. fig. 4. Empty frond : from a drawing by Professor Bailey. 



20. M. incisa (Kiitz.) ; lobes horizontal, basal ones truncate, with a 

 tooth at each angle ; end lobe convex, its angles acute. 



Euastrum Crux-Melitensis, Ehrenberg, Infus. t. 12. f. 3 c. (1838). 

 Euastrum incision, Brebisson, Meneghini, Synop. Desmid. in Linntea 1840, 



p. 216. Kiitzing, Phyc. Germ. p. 134. 

 Micrasterias incisa, Brebisson, in lit. (1846). 



Germany, Ehrenberg. Falaise, Brebisson. 



EUASTRUM, Ehr. 



19. E. cornutum (Kiitz.) ; segments three-lobed; terminal lobe cu- 

 neate, included between two process-like projections of the basal 

 portion. 



Euastrum cornutum, Kiitzing, Phycologia Germanica, p. 135 (184.5) ; in lit. 

 cum icone. 



Germany, Kiitzing. 



The frond resembles that of Euastrum crassum, but the outer angles of the 

 basal portion of each segment are prolonged into rostrate-like processes which 

 include the terminal lobe between them. 



Tab. XXXV. fig. 13. Frond : from a drawing by Professor Kiitzing. 



20. E. Pelta (Corda) ; segments quadrangular ; end margin with a 

 rounded protuberance at each corner ; lateral margins with a small 

 protuberance at the basal end and a larger one near the outer end. 



Cosmarium Pelta, Corda, Almanack de Carlsbad 1835, p. 121. t. 2. f. 25. 



Meneghini, Synop. Desmid. in Linncea 1840, p. 222. 

 Euastrum Pelta, Kiitzing, Phycologia Germanica, p. 135 (1845). 



Carlsbad, Corda. 



21. E. creuatum (Kiitzing). 



Euastnim crenatum, Kiitzing, Phycologia Germanica, p. 135 (1845). 

 Dalmatia, Kiitzing. 



This plant may be a variety of Euastrum elegans. 



Tab. XXXV. fig. 14. Frond: from a drawing by Professor Kiitzing. 



