514 Philippine Journal of Science »« 



The earliest described and well-established European species 

 of Volvox, V. globator Ehrenberg ('38) and V. aureus Ehrenberg 

 ('38), were described at length by Conn (75), whose colored 

 plate of V. globator has long been a classic for textbook and 

 handbook illustration, and by Klein ('89A and '90), who made 

 the largest contribution to the stock of pictures of V. aureus in 

 various stages and phases. His figures include at least one, 

 ('90) Plate 2, fig. 4, which is decidedly not of V. aureus, but 

 of one of the megalogonidiate species. At about the same time 

 Overton ('89) made a contribution to the knowledge of the life 

 history of the then known European species of Volvox. More 

 exact knowledge of the cell membranes of the somatic cells of the 

 two European species was the result of the work of Meyer ('95 

 and '96) who incidentally gave us what information we have 

 on his new species, V: tertius. His diagrammatic drawings of 

 the cell, membranes of V. globator and V. aureus are becoming 

 classic by reproduction in handbooks. I never look at these 

 drawings without feeling that it is improper to retain these 

 two species in the same genus. 



A species with a close affinity to V. globator was described 

 by Powers ('08) from Nebraska under the name V, per globator. 

 The somatic protoplasts of this species are highly stellate and 

 connected with their neighbors. The same is true of another 

 species described by West ('10) from Rhodesia under the name 

 V. rousseleti. In this one the cells are smaller and more 

 numerous. 



My own Philippine material 6 contains at least two species, 

 both labeled with new names in my note books and in the al- 

 bums containing their photomicrographs, which are more or less 

 closely similar to V. globator, V. perglobator, and V. rousseleti. 

 In 1914 my collection of slides contained two excellent gly- 

 cerin mounts of Volvox aureus (labeled V. minor) marked 

 "4-16-96." The date indicates that the specimens were collected 

 at Stanford University, California. They were under cover 

 glasses sealed to the slides with Brunswick black which had 

 cracked and become loosened. They had been fixed and stained 

 with picro-nigrosin and the glycerin was slightly tinged with 

 the picric acid. The staining had been very light. The speci- 

 mens were mostly in beautiful condition after eighteen years 

 under the covers, but the glycerin had partly escaped and was 



'Some material collected in Borneo by Mary Strong Clemens contains 

 a similar species. 



