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SOME NEW AFRICAN SPECIES OF VOLVOX. 



By G. 8. West, M.A., D.Sc, F.L.S., Professor of Botany at the 



University of Birmingham. 



{Communicated by Mr. C. F. Rousselet, Octoher 2oth, 1910.) 



The present short paper is largely a report on a number of slides 

 of Volvox recently submitted to me for examination by Mr. C F. 

 Rousselet. They embraced a series of specimens of Volvox 

 globaior, Volvox aureus, and several other forms of considerable 

 interest. 



The characters of the two European species, V. glohator and 

 V. aureus, are now very well known and their specific distinction 

 clearly established. This was due in the first instance to the 

 researches of Klein,* and his investigations have been repeatedly 

 confirmed. Overton t has also pointed out further distinctions. 

 In this country Hick t was the first to direct attention to the 

 fact that these two distinct species were widely distributed. 

 The distinguishing features are for the most part in the sexual 

 organs and ripe oospores, although each species can be definitely 

 recognised by the structure of the vegetative colony. 



It is not at all uncommon to find the two species mixed in the 

 same pool or pond, and perhaps the appended synopsis of their 

 distinctive characters may prove useful. In both species the 

 vegetative (or asexual) colonies are globular and the male 

 colonies ovoid, but in V. glohator the female colonies are almost 

 invariably globose, while in V. aureus they may occasionally 

 be ovoid. 



* Klein in Pringsheim's Jahrh. flir ivissensch. Botan., xx., 1889. 



f Uverton in Botan. Centralhl., xxix., 1889. 



\ Hick in Trans. Manchester Microscojncal Society, 1891. 



