Ph3'siologie. — Palaeontologie. 269 



White, J., The proteolvtic enzj'me of Drosera. (Proc. Roy. 

 Soc. LXXXIII B. p. 134—139. 1910.) 



The authoress has investigated the proteolytic enzyme of four 

 species of Drosera (D. auriculata, Mensiesii, peltata, Whittakeri) and 

 tinds that a pepsin-like enz\'me occurs in all cases, but is not asso- 

 ciated with an}' peptolytic or tr5'ptic enzyme. Peptic digestion occur- 

 red either in acid, neutral, or acid media, all tests giving a good 

 biiiret reaction for peptones, but in no case could the faintest trace 

 of amides be found with the tryptophane reaction. This is appa- 

 rently the case recorded of a peptase occurring in plants unasso- 

 ciated with ereptase, and the enzyme is present as such, not in the 

 form of z^'mogen. The leaves were found to be capable of absorbing 

 dissolved peptones from liquids placed on their surfaces in a few 

 hours. F. Cavers (London). 



Arber, E. A. N., On the earlier Mesozoic Floras of New 

 Zealand. (Proc. Cambridge Phil. Soc. XVH. 1. p. 122—131. 1913.) 



A summary of what is known of the Pre-cretaceous floras of 

 New Zealand. The author gives short, critical notes on some of 

 the older records of Unger, Hector, Ettingshausen & Crie, 

 and concludes that there are but ten already described, valid spe- 

 cies, with three or four other species which may have to have new 

 specific names. Long lists of synonyms and nomina nuda follow. 



M. C. Stopes. 



Dachnowski, A., Peat Deposits of Ohio, Their Origin For- 

 mation and Uses. (Bull. XVI. 4tJi Ser. Geol. Survey Ohio. 424 pp. 

 8 pl. 29 textfig. 33 tables 1912.) 



This important publication, issued in Cooperation with the U.S. 

 Bureau of Mines, considers the varieties of peat, their quality, ge- 

 neral distribution in Ohio and in the United States. A detailed 

 survey of the counties with reference to the occurrence of peat 

 deposits occupies 110 pages of the report. Chapter IV by Charles 

 A. Davis (pages 145 — 195) gives an account of the uses of peat, as 

 fuel and as a row material for products other than fuel, such as , 

 alcohol, dyestuffs, paper, woven fabrics, artificial wood, etc. 



Part II by Dr. Dachnowski is concerned with the origin of peat 

 deposits and their Vegetation (Chap. V), the formation and develop- 

 ment of Ohio peat deposits (Chap. VI). Here is described the ecologic 

 Vegetation units, the succession of Vegetation in Ohio lakes and 

 peat deposits (open water, marginal, shore, bog and mesophytic 

 forest successions), secondary successions. Chapter VII deals with 

 the ancient peat deposits of Ohio and their ecologic conditions for 

 growth, especially the coal measures and their Vegetation, and 

 what conditions determined xeromorphy and the origin of land 

 plants. 



Part III, also by Dachnowski, is in line with the work which 

 the author has made especiallj'' his line of research. It deals after a 

 preliminarj'' chapter on climatic conditions with the physiologic 

 effects of peat, such as the harmful organic constituents of peat, 

 peat toxins their efifect upon three growth, peat toxins their effect 

 upon soils, the nature of the absorption and tolerence of plants in 

 bogs. Chapter X is concerned with the bacterial flora, as a factor 

 in peat formation, and the last Chapter (XI) considers the chemic 



