Physiologie. 317 



bord de la mer. Contribution ä l'etude des causes 

 phj^siologiques du buissonnement. (Trav Biol. veget., livre 

 dedie ä Gaston Bonnier. p. 135—149, et Rev. gen. Bot. XXVbis. 

 1914.) 



L'auteur etudie les deformations subies par VErica vagans 

 croissant au bord de la mer et subissant l'influence du vent marin. 



Les causes de ces deformations sont les suivantes: 



P Le vent agit en courbant mecaniquement les jeunes rameaux, 

 en entravant directement et indirectement la croissance de ces ra- 

 meaux, en tuant le sommet des pousses trop exposes. 



2<^ La plante reagit en tentant de redresser ses rameaux, en 

 accroissant le diametre de ces derniers et en ömettant des pousses 

 nouvelles et nombreuses audessous des sommets mortifies. 



3° Le grand rapprochement des rameaux resultant des actions 

 pr^cedentes intervient secondairement en diminuant la quantiie de 

 lumiere utilisable par les parties non superficielles de la plante. 



R. Combes. 



Osterhout, W, J. V., Reversible changes in permeability 

 produced by electroly tes. (Science N. S. XXXVL p. 350— 35L'. 

 1916.) 



In continuation of work previously reported the writer finds 

 that permeability of cells of Laminaria may be alternately increased 

 and decreased by means of lithium nitrate and calcium Chloride 

 without evidence of an injurious effect on the plant tissue. 



W. H. Emig (St. Louis). 



Sackett, W. G., The ammonifying efficiency of certain 

 Colorado soils. (ßul. Colo. Agr. Coli. 184. p. 1-24. 1912.) 



A series of cultural experiments on soils affected with the "niter 

 trouble" and a comparison of these results with the ammonifying 

 power of normal soils from other localities shows that these Colo- 

 rado soils are much the more efficient in transforming the nitrogen 

 inte ammonia. The nitrogen was furnished in different experiments 

 by cotton-seed meal, dried blood, alfalfa meal, or flax-seed meal. 

 The maximum per cent of ammonia produced in seven days from 

 106 mg. of nitrogen, was 51.98 per cent when cotton-seed meal was 

 used, 52 64 per cent with dried blood, and 34.85 per cent with 

 flax-seed meal. L. 0. Overholts (St. Louis). 



Schniedep, E. C, A nutrition investigation on the inso- 

 luble carbohydrates or marc ofthe apple. (Amer. Journ. 

 Physiol. XXX. p. 258—270. 1912.) 



The work done by other investigators on various phases of the 

 subject is outlined more or less briefly under the following heads: 

 The composition of the apple and its marc; bacteriological studies; 

 enzyme studies; digestion and utilization. Then the author gives 

 his own findings, which in brief are as follows: A pectin from the 

 water-insoluble portion, or marc, of the apple gave on analysis 

 about 57 per cent of reducing sugar, as dextrose, 35 per cent pen- 

 tosans, and 45 per cent galactans; faecal bacteria, both aerobic and 

 anaerobic, are capable of destroying the hemicelluloses of marc, 

 pectin, and the pentosan and galactan of the pectin, but the enzy- 

 mes tried were not capable of hydrolyzing either marc or its pectin, 



