io6 



NATURE 



[November 29 1900 



satisfactory. We have now however a paper before us, 

 by Dr. A. Mayr, read at the Bombay Medical Union, 

 April 21, 1900, dealing with more recent trials, in which 

 there were 38"2 per cent, of recoveries in 403 patients 

 treated, the recoveries of patients under ordinary treat- 

 ment being I9"5 per cent. 



Whether the nucleo-proteid be used as a prophylactic 

 to inoculate persons or to immunise horses to prepare a 

 curative serum, it is evident that the antitoxin given rise 

 to in the person or the horse is an antitoxin against the 

 poisonous nucleo-proteid ; the stakes in the race for 

 recovery are all placed on the nucleo-proteid. 



But it is not improbable that the metabolic products 

 formed by the plague microbe in the medium it grows on 

 — be it the body or an artificial medium — require to be 

 immunised against, and herein lies the distinction between 

 Haflfkine's prophylactic and Lustig's nucleo-proteid used 

 as a prophylactic. Hafifkine uses the bodies of the bacilli 

 together with the broth they have grown in, for he con- 

 siders the broth acted upon by their growth to be useful 

 if not essential. This has been shown to be the case in 

 experiments on animals by Dr. Balfour Stewart {British 

 Medical Journal, March 3, igoo). 



Lustig's nucleo-proteid prophylactic has some technical 

 advantages in its preparation over Haflfkine's, but for the 

 reasons pointed out above it is not likely to be as 

 efficacious. C. B. S. 



A Monograph of the Erysiphaceae. By Ernest S. 



Salmon, F. L.S. " Memoirs" of the Torrey Botanical 



Club. Vol ix., Pp.292. (New York : 1900). 

 The Torrey Botanical Club has performed a valuable 

 service to mycologists in the publication of this excellent 

 monograph of the Erysiphaceae, a group of parasitic 

 fungi causing the diseases known as white mildew, pow- 

 dery mildew, blight, Mehlthnu, blanc, &c. In their coni- 

 dial or " oidium " stage they are common throughout 

 the summer on various host-plants, such as roses, hops, 

 vines, peas, maples, and many wild plants, giving a 

 mealy appearance to the part infected ; while in the later 

 summer or autumn the perfect ascigerous form is pro- 

 duced in the form of dark brown or black spots, con- 

 sisting of peritheces containing ascospores, and usually 

 provided with characteristic appendages. 



The number of known species of this well differentiated 

 group of fungi is not large ; the author describes forty- 

 nine, including a very few new ones, in addition to a 

 number of well-marked varieties. These are arranged 

 in six genera, Podosphjera, Sphyerotheca, Uncinula, 

 Microsphaera, Erysiphe, and Phyllactinia. Great con- 

 fusion exists in the nomenclature of the European 

 species, and the author corrects several prevalent errors. 

 He regards the ascus as the result of a true sexual pro- 

 cess, and does not support Dangeard's view that the 

 fusion of the nuclei in the young ascus is of sexual sig- 

 nification. 



The monograph is illustrated by nine plates, and is 

 supplemented by a very copious bibliography, in which 

 no less than 400 distinct works or papers are referred to, 

 and a host-index of the plants attacked by these fungi. 



A. W. B. 



An Old Man's Holidays. By The Amateur Angler. 



Pp. xii-l-140. (London: Sampson Low, Marston and 



Co., 1900.) 

 " An Am.\teur Angler " is an observer of nature as well 

 as an enthusiastic Waltonian, the result being that these 

 holiday sketches contain here and there an observation 

 of interest to naturalists. Referring to the growing 

 scarcity of kingfishers he says, " This is partly owing to 

 the fact that they have the credit of being destructive 

 enemies of young trout ; the fact is, they do feed on little 

 fishes, but not so much on trout as on minnows, dace, 

 sticklebacks, miller's thumbs, and even leeches " The 

 book contains several illustrations of rural scenes. 



NO. 1622, VOL. 63] 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for opinions ex- 

 pressed by his correspondents. Neither can he undertake 

 to return, or to correspond with the writers of, rejected 

 manuscripts intended for this or any other part of Nature. 

 No notice is taken of anonymous communications.^ 



Buchner's Zymase. 



The most recently issued number of the Proceedings of the 

 Royal Society (No. 438) contains a paper by Dr. McFadyen, 

 Dr. Morris and Mr. Rowland on the subject of Buchner's 

 zymase, which is held by many observers to be the alcohol- 

 producing enzyme of yeast. 



The authors describe a long series of experiments which they 

 have carried out, partly on Buchner's lines, and partly by new 

 methods of their own. They find, as Buchner and other inves- 

 tigators have done, that yeast will, under proper conditions, yield 

 up an extract which can set up alcoholic fermentation in a solu- 

 tion of cane sugar. Many very interesting points have come 

 out during the progress of their work, the explanation of which 

 is not at present very obvious ; their conclusion, however, seems 

 to call for a very careful scrutiny of the operations, especially as 

 it has been advanced by other writers also. They state at the 

 end of their paper that their experiments cause them to doubt 

 the existence of an enzyme, and lead them rather "in the 

 direction of a theory which refers the phenomenon to the vital 

 activity of the yeast-cell protoplasm" (p. 265). 



In reviewing their experiments it is noticeable thit, in their 

 preparation, the yeast was mixed with a certain proportion of 

 kieselguhr, and subjected in this condition to the enormous 

 pressure of 200-300 atmospheres (p. 252). The liquid thus 

 expressed was capable of filtration under pressure through a 

 Chamberland or Berkefeld filter (p. 259) without losing its pro- 

 perties, though the process decreased its power. It was miscible 

 with, or soluble in, a small quantity of water or solution of cane- 

 sugar without being altogether destroyed, though too much of 

 the solvent inhibited its action (p. 262). The experiments were 

 conducted thioughout in the presence of antiseptics, «iv:h as 

 I per cent, of sodium arsenite, thymol, or toluol (p. 254). 



It will be difficult for physiologists to accept a conception of 

 a protoplasm which is not destroyed by such a pressure as was 

 used, and which afterwards becomes to some extent soluble in 

 water, or, at any rate, miscible with it, which can be filtered 

 through a porcelain filter without destruction, and which can 

 carry on an anabolic and subsequently a katabolic process 

 (p. 265) in the presence of such antiseptics as were used. 



The authors say in an earlier part of the paper (p. 253^ that 

 such a kieselguhr "sponge" as they obtained during the ex- 

 traction of the yeast was capable of retaining almost entirely tlie 

 globulins of eggs, and, to a large extent, albumin and serum 

 proteids. It seems strange after this to find them holding the 

 view that protoplasm itself was not retained by such a " sponge." 



It is a little difficult to reconcile their concluding theory of a 

 fluid protoplasm with their statement (p. 253) that the juice they 

 obtained and used was in every case far removed in nature from 

 the condition in which it existed when alive in the yeast cell, 

 even if one were to admit that the juice was ever living at all. 

 Is it possible, in their opinion, for the anabolic and katabolic 

 aclivities of protoplasm to be manifested in such a juice as they 

 describe in those words ? Yet their final hypothesis is that the 

 yeast juice exhibits the " vital activity of the yeast-cell proto- 

 plasm." 



I venture to disagree with their conclusion. In my own ex- 

 periments, which were published in the Annals of Botany, 

 vol. xii (1898), p. 491, I found that an active preparation could 

 be obtained by grinding the yeast with kieselguhr in such pro- 

 portion that a perfectly dry impalpable powder resulted, and 

 then extracting the latter with a solution of cane-sugar. It is 

 hardly credible that protoplasm without the protection of cell- 

 walls, can resist desiccation. The action of the extract in my 

 experiments, as in theirs, was considerable in the presence of 

 antiseptics which, in the proportions used, were inevitably and 

 rapidly fatal to the life of protoplasm. 



Cambridge, November 19. J. Reynolds Green. 



Euclid i. 32 Corr. 



Mr. Tucker is right (p. 58) in his conjecture that Clavius 

 was not the first to publish these corollaries. 



References:—?. Ramus (ob. 1572), "Scholar™ Math'"' Libri 

 unus et triginta. A Lazaro Sckonero recogniti et emendati," 



