112 Physiologie. — Algae. 



The author's results from his own researches on yeast are 

 as follows: 1. Dilute yeast-mixtures or aqueous extracts rapidly 

 eifect peptolysis but do not digest fibrin. 2. Extracts of yeast 

 in dilute Solutions of sodium chloride readily digest fibrin. 

 3. Peptolysis and peptonization are influenced in the same 

 manner, but not in the same degree by the addition of acid 

 or alkali. From these facts the conclusion is drawn that yeast 

 contains two proteases, one readily soluble in water and ex- 

 clusively peptoiytic; the other less soluble in water, but readily 

 soluble in 2° o sodium chloride Solutions, and having a pepto- 

 nizing character. 



Similar results and conclusions are obtained from experi- 

 ments on AgariCUS. E. Drabble (London). 



Rathbone, May, Notes on Myrlactis Areschougü and Coilo- 

 desme californlca. (Journal of the Linnean Society. Vol. XXXV. 

 Botany. No. 248. May 1904. p. 670—675. PI. 24.) 



The author describes briefly the work hitherto done on M. Are- 

 schougü Batters (— Elachista Areschougü Crouan), especially that of 

 Mons. Sauvageau. She finds that the tufts of the alga are not ne- 

 cessarily connected with the cryptostomata of Himanthalia lorea, the 

 host plant on which it grows ; she has been unable to trace the manner 

 of the penetration but agrees with Mons. Sauvageau in supposing that 

 infection takes place by means of zoospores. She has traced rhizoids 

 of M. Areschougü for some distance among the loose central tissue of 

 Himanthalia and feels little doubt that these rhizoids act as stolons for 

 propagating the plant. In M. stellulata Batt. she has traced the rhizoids 

 irom tuft to tuft along the host tissue, shewing that at least in that spe- 

 cies the connecting stolons exist. The rhizoids of M. Areschougü are 

 easily distinguished in fresh material by their pinkish-brown colour and 

 in spirit-material their course can be traced by staining with Hoff- 

 m a n 's blue, which stains the rhizoids more deeply than the cells of the 

 host, Active cell-division of the host-cells at the base and sides of M. 

 Areschougü was often seen and it was noticed that they stain rather 

 differently from the adjoining cells. 



A short description is given of the penetrating rhizoids of Coilo- 

 desme californica Kjellm., which do not send out long wandering filaments 

 but penetrate in a dense mass the walls of the host cells immediately 

 below its base. These penetrating filaments have been overlooked in 

 previous descriptions ot the plant. Among the figures given is one 

 of the plurilocular sporangia of Myriactis stellulata Batt., which were 

 described and figured by Harvey in his Phycologia Brittanica as para- 

 nemata. E. S. Gepp-Barton. 



Saunders, De Alton, The Algae of the Expedition. 

 (Harriman Alaska Expedition. V. Cryptogamic Botany. 

 March 26, 1904. p. 155—250. pl. 10—29.) 



A reprint from the original electrotype plates used in the publi- 

 cation of this paper, under a slightly different title in Proceedings of the 

 Washington Academy of Sciences (Vol. III. November 15, 1901. p. 391 

 — 48b.) The original pagination of text and plates is indicated in brackets. 

 The article is prefaced by a list of errata. Maxon. 



