ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 455 



the fact that the experiments of this writer extended over too long a 

 period after the death of the parts of the plant in question, when the pro- 

 duction of carbonic acid has set in, resulting from the presence of bacteria 

 or ordinary putrefaction. 



Assimilation in Plants destitute of Chlorophyll.* — Herr F. Hueppe 

 has determined that a nitrifying bacterium which presents no peculiarities 

 in the spectroscope, possesses the power of making use of the carbon in 

 carbon dioxide for the production of carbohydrates, ammonium carbonate 

 being broken up into ammonia, formic aldehyd, and oxygen ; the oxygen 

 thus set free then, in the nascent condition, oxidizing the ammonia into 

 nitric acid, and causing the aldehyd to split up into cellulose and water. 

 Whether sugar was formed in the first place was not determined. 



Synthesis of Albuminoids.! — M. Chrapowitzki caused seedlings of 

 Phaseolus, Lupinus, Pisum, Cucurbita, Helianthus, Cannabis, Zea, and 

 Pinus, -to use up the whole of their reserve albuminoids by water-culture 

 in solutions of mineral salts containing no nitrogen. If then trans- 

 ferred to another solution containing nitrates, a gradual fresh forma- 

 tion of albuminoids may be observed in the chlorophyll-grains, com- 

 mencing in from three to six days. The author concludes that the 

 chlorophyll-grains are the seat of the formation not only of the carbo- 

 hydrates, but also of the albuminoids. 



Relation between the Heat and the Carbonic Acid given off by 

 Plants in Respiration. J — Dr. H. Rodewald has attempted to investigate, 

 by means of caloria or chambers constructed for the purpose, the amount 

 of heat given off by plants in the process of respiration, comparing this 

 with the quantity of carbonic acid eliminated. The objects experimented 

 on were ripening apples and potatoes. He finds that always by far the 

 larger part of the energy set free by respiration is given off in the form 

 of heat. Supposing the whole of the carbonic acid to result from the 

 combustion of starch, he found the actual quantity of heat developed to 

 be 92*2 per cent, of that which would be due theoretically to the con- 

 sumption of the corresponding amount of starch. The contrivances by 

 which the vitiation of the results through errors was prevented are 

 described in detail. The loss of heat from transpiration could be esti- 

 mated from the loss of weight, from which the quantity of carbon con- 

 sumed in respiration must be deducted. The specific heat of the body 

 experimented on was determined by a calorimeter to be about 0*924. 

 The quantity of carbonic acid evolved was estimated at the same time 

 in all the experiments. 



Duration of the Apical Growth of the Leaf. § — Herr P. Sonntag 

 discusses the correctness of the view that axial and foliar structures 

 may be distinguished from one another by the difference in the mode of 

 growth, whether basal or apical. The termination of apical growth may 

 be inferred from the formation of hairs on the growing point, and from 

 the development of intercellular spaces in the apical tissue. 



Among Vascular Cryptogams we find that in most ferns apical growth 

 of the leaves has ceased when all the lateral segments have been formed, 



* Versainral. Deutsch. Naturf. u. Aerzte, Wiesbaden, Sept. 21, 1887. See Bot. 

 Centralbl., xxxiii. (1888) p. 60. 



t Bull. Acad. Imp. Sci. St. Pe'tersbourg, xxxii. (1887) pp. 96-8. 



% Pringsheim's Jahrb. f. Wiss. Bot., xviii. (1887) pp. 263-345 (1 pi.). 



§ Ibid., pp. 236-62 (1 pi.). 



