2 TUFTS COLLEGE STUDIES, VOL. IV, No. 7 



muda. Other authors and contributors are recorded in their 

 proper places. 



The most important general work appearing during the past 

 five years is Die Siisswasser- Flora Deutschlands, Oesterrek-hs 

 und der Schweiz, issued by Pascher of Prag, really a series of 

 monographs by the best specialists of continental Europe, cov- 

 ering all vegetation from flowering plants down, to be found 

 in fresh water. Beside recording all, and figuring nearly all, 

 found in the regions named, it has at least references to most 

 species of other regions with similar conditions ; it is prac- 

 tically indispensable to any careful student. The student will, 

 however, regret that the condensed form, in one way an advan- 

 tage, has excluded all references to original descriptions and 

 most synonymy. As no citations are given, it is impossible to 

 determine when a combination is used for the first time, as is 

 certainly sometimes the case. Part V, Tetrasporales, Proto- 

 coccales, Part VI, Ulothricales, Microsporales, Oedogoniales, 

 Part IX, Zygnemales, have been issued ; Parts IV, Volvocales, 

 VII, Siphonales, XI, Heterokontse, are still to come. 



West, 1916, contains a system of classification of all the 

 green algae, with characters of genera and higher divisions ; 

 it differs considerably in details from previous classifications. 

 Attention has been given to it in cases where genera not before 

 known in North America are now reported, but no attempt has 

 been made to rearrange genera already known here. In ^m 

 eral, specific names have not been changed from those used in 

 1909 and 1912, when the change was due to the dis< 

 an older name than the one hitherto prevailing ; nor has record 

 been made of extensions of range. 



Citations have been made in the same manner as in tilt- 

 original paper and the first supplement; all works not already 

 included in the lists given with those papers will be found in 

 the list at the end of this paper. In general the seco-nd sup- 

 plement follows the plan of the first, as stated on p. 70 of the 

 latter. No attempt has been made to revise the keys to the 

 genera, as a paper by the writer will soon be issued in the Tufts 

 College Studies, giving a general key to the genera of North 



_3 j:Jb 



