462 Algae. 



MARQUAND, E. D., Additions to the Flora of Alderney. 



(Guernsey Society of Natural Science and Local Research. 



Report and Transactions 1902. Published Guernsey. 1903. 



p. 145—148.) 



Contains, among other lists, one of 62 marine algae, with the name 

 of the locality where each species occurs. E. S. Gepp-Barton. 



MARQUAND, E. D., Further additions to the Flora of 



Alderney. (Guernsey Society of Natural Science and Local 



Research. Report and Transactions 1903. Published Guernsey 



1904. p. 266—271.) 



Contains lists of 14 marine algae, 63 fresh-water algae and 9 Des- 

 midiaceae. E. S. Gepp-Barton. 



West, W. and West, G. S., A monograph of the British 

 Desmidiaceae. Vol. I. (Printed for the Ray Society. London 

 1904. XXXVI, 224 pp. XXXII plates.) 



In a preface of a few pages the authors give a short 

 historical account of the work previously done on this subject 

 by various authors. The last book on British Desmids was 

 published in 1387 in which were described 290 species and 

 48 varieties. The number of species described and figured 

 in the present monograph will be approximately 690 and 

 the number of varieties about 450, being an increase of 

 400 species and 402 varieties, the majority of which have been 

 added by Messrs. West themselves. A long bibliographical 

 list is followed by an Introduction in which the authors give 

 an account of Desmids in general and compare different genera 

 with each other. The structure is described under the headings 

 of cell-wall, cell-protoplasm, chloroplasts and nucleus. Other 

 subjects discussed are Variation, Locomotion, Vegetative Re- 

 production, Asexual Reproduction, Sexual Reproduction, Phylo- 

 genese Relationships of the Desmidiaceae, Occurrence and 

 Distribution, Collection and Preservation, Examination and 

 Specific Determination. The Phylogeny of the Genera of Des- 

 mids is illustrated by a diagram, shewing the lines of deve- 

 lopment and the connection between the genera. Then follows 

 the systematic treatment. The arrangement of the genera is 

 based Lipon the scheme of evolution already published by one 

 of the authors and upon certain recent investigations of Lüt ke- 

 rn ü 1 1 e r. The names Pleurotaeniopsis and Pleiirentegium as 

 genera are not retained. An analytical key is given to all the 

 known genera of Desmids, five of which have not been recor- 

 ded from the B r i t i s h I s 1 e s. It is suggested that Cosmarium 

 and Staurastrum may at some future time have to be split up 

 into smaller genera, but the authors consider that they are not 

 yet justified in doing this. One new species is described Meso- 

 taenium truncatum, and 13 new varieties of already existing 

 species. The diagnosis of each species is preceded by syno- 



