790 



SCIENCE 



[N. S. Vol. XXXIX. No. 1013 



remarks on photochemistry, colloids and re- 

 search work in Great Britain. Altogether this 

 is a very readable book and all the more so 

 because of the continuity of plan, which is 

 quite unusual. Most writers of historical out- 

 lines content themselves — or are forced to con- 

 tent themselves — with isolated chapters. It 

 is really quite a feat to have avoided this 

 danger to so great an extent as Sir William 

 Tilden has done. 



The reviewer is entirely in sympathy with 

 the contention, in the preface, that students 

 should not only know the names of the lead- 

 ers of scientific thought, but should perceive 

 correctly the connection between their discov- 

 eries and the general progress of their science. 

 In order to bring this about, a series of bio- 

 graphical notes has been appended to each 

 chapter. In these notes are given a brief 

 sketch of the life and work of every deceased 

 chemist or physicist who has contributed sub- 

 stantially to the progress thus far accom- 

 plished. 



Wilder D. Bancroft 



BOTANICAL NOTES 

 PROTOCOCCOS, NOT PLEUROCOCCUS 



In a recent number of Nyt Magazin for 

 Naturvidenskaberne (Christiania) N. Wille 

 gives the results of his studies of the actual 

 specimens of certain lower green algae pre- 

 pared by C. A. Agardh, and still preserved in 

 the herbarium of the University of Lund, 

 Sweden. One outcome of these is the settle- 

 ment of the question as to whether or not the 

 name Protococcus is still valid. As every 

 teacher knows there has been a strong tide 

 against the use of the name Protococcus for 

 the common green slime of tree-trunks and 

 walls, the preferred name being Pleurococcus. 

 In the paper under consideration the author 

 first gives a summary history of the nomencla- 

 tural tangle which has arisen. In 1824 C. A. 

 Agardh named a certain plant Protococcus 

 viridis. In 1842 J. Meneghini, not knowing 

 Agardh's plants, proposed the name Pleurococ- 

 cus, and included blue-green as well as green 

 species, and among the latter he included the 

 plants named Protococcus viridis by Agardh. 



Other forms of confusion resulted from this 

 initial blunder of Meneghini's but what is 

 here given is sufficient to warrant Wille's con- 

 clusion : 



It is clear that in order to disentangle such a 

 confused mass of synonyms one must go back to 

 the original specimens to determine what C. A. 

 Agardh really understood by his species Protococ- 

 cus viridis. 



So he examined the original specimens and 

 found that the specimens labeled Protococcus 

 viridis are what later authors have called 

 Pleurococcus. This fact requires, as Wille 

 says, that " this species must therefore be 

 called Protococcus viridis." 



Since Pleurococcus was used by Meneghini 

 for blue-green and also gTeen algse that name 

 is left badly discredited, and must doubtless 

 fall into synonymy. 



SHORT NOTES 



SoiiE recent systematic papers are: A Con- 

 sideration of Structure in Eelation to Genera 

 of Polyporaceae, by Doctor Adeline Ames 

 (Ann. Mycol, Vol. XI.), including a key to, 

 and descriptions of sixteen genera, with four 

 half-tone plates; New Fucaceae, by N. I. 

 Gardner (Calif. Univ. Pub., Vol. 4), contain- 

 ing descriptions of some western rockweeds 

 and their close allies, and accompanied by 

 eighteen haK-tone plates of excellent photo- 

 graphs of the plants described. 



Bulletins 284 and 285 of the Bureau of 

 Plant Industry of the U. S. Department of 

 Agriculture on the Water Requirement of 

 Plant deal with some of the scientific facts 

 that underlie the practical aspects of agricul- 

 ture. In the first the joint authors, L. J. 

 Briggs and H. L. Shantz, report in detail upon 

 their investigations made at the dry-land ex- 

 periment station at Akron, in northeastern 

 Colorado, in the years 1910 and 1911. The 

 bulletin is a valuable contribution to the phys- 

 iology of the water loss sustained by plants 

 under arid conditions. In the second bulletin 

 the same authors have rendered a most wel- 

 come service to plant physiologists by pre- 

 senting in summary form a review of the liter- 

 ature of the water requirement and water loss 



