THE 



JOURNAL OF B O T A N Y 



BEITISH AND FOKEIGN. 



ALGOLOGICAL NOTES— XVIII-XXIII. 

 By G. S. West, M.A., D.Sc, F.L.S. 



BUTAINICAU 



nAi(!»H'' 



XVIII. — Chlamydomonas miceoscopica, nov. nom. 



In Note XIV of this series a new species of the Volvocaceas 

 was described under the name of Chlamydomonas gracilis.'''- I now 

 find that the specific name ''gracilis'' has akeady been utihsed 

 for an entirely different species of Chlamydomonas by Snow in 

 1903. t Hence the minute species from Sutton Park, Warwick- 

 shire, requires another specific name, and I suggest Chlamydomonas 

 microscojjica as a suitable one. Snow's paper on the Plankton 

 Algae of Lake Erie was one of the few papers dealing with fresh- 

 water phytoplankton that I had not seen, and it is through the 

 kindness of Mr. F. S. Collins, of North Eastham, Mass., that I 

 have at last obtained a copy of it. 



XIX. — The Genus Peotococcus Agardh. 



Wille has recently shown | that the genus Protococcus Agardh 

 (1824) § stands on a firm basis and must be upheld. He has care- 

 fully examined Agardh's original specimens of Protococcus viridis, 

 and has found them to be identical with the common Alga usually 

 known as " Pleurococcus vidgaris," an Alga which Chodat || recently 

 described under the name of Pleurococcus Ndgelii. This note so 

 recently published by Wllle is of considerable general and taxo- 

 nomic importance, since it finally decides that this exceedingly 

 common Alga of damp temperate regions must in future be known 

 as Protococc2cs viridis. Likewise it determines the scope of the 

 family Protococcaceae, which in the future cannot be used in the 



* G. S. West, "Algological Notes, XIV— XVII," Journ.Bot., March, 1915, 



p. 77. 



t Julia W. Snow, "The Plankton Algae of Lake Erie," Bull. U. S. Fish. 

 Commission for 1902, Washington (1903), p. 388, t. 1, f. 1. 



: N. Wille. " Algologische Notizen XXII— XXIV," Nyt Magazin for 

 Naturvidenskaberne, li, 1913. 



§ C. A. Agardh. Systema Algarmn, Lundae, 1824, p. 13. 



II K. Chodat, Algues Vertes de la Suisse, Berne, 1902, p. 281. 



Journal of Botany. — Vol. 54. [January, 1916.] b 



