238 NOTES AND CO MAI E NTS [octobek 



of Physiology " from that expressed in Green's " Prolegomena," or in 

 Newman's " Sermons," or in Whistler's " Gentle Art," or in Meredith's 

 " Ballads of the Earth." Altogether apart from subject-matter, the 

 intellectual note of these is quite different from that which characterises 

 the immortal text-book referred to, and what we wished was that the 

 Professor had told us what his particularly well-marked differentiating 

 feature — obscured by the word " scientific " — really meant. 



Much more satisfactory was the concluding part of the address, in 

 which the President discussed the solidarity and internationalism of 

 science. " The man of science," he said, " cannot sit by himself in his 

 own cave, weaving out results by his own efforts, unaided by others, 

 heedless of what others have done or are doing. He is but a bit of a 

 great system, a joint in a great machine, and he can only work aright 

 when he is in due touch with his fellow-workers. If his labour is to 

 be what it ought to be, and is to have the weight which it ought to 

 have, he must know what is being done, not by himself, but by others, 

 and by others not of his own land and speaking his tongue only, but 

 also of other lands and other tongues." That this is being increasingly 

 recognised is made evident in many ways — by international congresses 

 and bibliographies, by international co-operation in great enterprises 

 like the Antarctic Expedition, and in smaller endeavours like the pro- 

 duction of Natural Science. 



More Pleurococcus. 



Another filament-forming Alga, to which its discoverer, Miss Snow 

 {Annals of Botany, vol. xiii. No. 4, p. 189), has provisionally given the 

 name Pseudo-Pleurococcus, has been separated from the aggregate of 

 small unicellular green forms, so long known under the collective name 

 of Pleurococcus vulgaris. The new form differs in the unicellular state 

 from the true Pleurococcus vulgaris, which we are glad to see Miss 

 Snow still recognises as a constant non-filament-forming species, by 

 the possession of a pyrenoid and of a lateral aperture in the chloro- 

 plast, while it has the power of forming filaments when grown in 

 certain nutritive solutions. 



It appears also to be distinct from the filamentous form of Pleuro- 

 coccus described by Chodat, in which the pyrenoid was absent, and 

 which could not be distinguished in the unicellular state from the true 

 Pleurococcus. In truth, the layer of green unicellular organisms so 

 frequently met with on the bark of trees, etc., seems to consist, not of 

 a single polymorphic species, but rather of a considerable number of 

 real species, which may be isolated from one another only by the 

 employment of certain modifications of the well-known methods of 

 bacteriology, especially by rigid attention to the sterility of cultures. 



