734 EXPERIMENT STATION RECORD. 



tliat used by Lamarliere and Verschaffelt. By its use, the transpiration of a 

 jilant under known and constant conditions can be accurately measured, and it 

 is possible to demonstrate individual differences in the transi)iration rates in 

 diflerent plants of the same species. This apparatus is designed for securing 

 data as a basis for plant selection and breeding. 



A new respiration calorimeter, G. J. Pierce {Bot. Gaz., ^6 (1908), No. 3, pp. 

 193-202). — The author describes experiments with Dewar flasks, both silvered 

 and unsilvered, in which the temperature of germinating peas, growing yeasts, 

 etc., was determined. These flasks come in several shapes and appear well 

 adapted for use as respiration calorimeters where the heat and energy of 

 respiration are to be determined. For class use they are said to be decidedly 

 better than any forms of apparatus commonly in use. 



On endospermic respiration in certain seeds, 1*\ Stoward (Ann. Bot. [Lon- 

 don}, 22 {1908), No. 87, pp. Jil5-It'i8). — Experiments with barley, maize, and 

 castor beans have been carried on to determine whether or not the cells of the 

 endosperm possess vitality. The view generally accepted is that endosperms of 

 Graminejfi possess vitality and are endowed with the capacity of autodigestion. 



The experiments, which are described at considerable length, lead to the 

 conclusion that the pure endosperm tissue of both barley and maize is capable 

 of manifesting a gaseous exchange of a respiratory cliaracter. Whether this 

 manifestation of respiratory activity is wdiolly or in part due to the vital activ- 

 ity of living protoplasm, or to the agency of respiratory enzyms, is yet 

 undecided. 



The evidence of the possession of vitality by the aleurone layer, which has 

 hitherto been based on cytological and enzymic data, is substantiated by the 

 results of the author's investigations. 



The vitality and self-digestion of the endosperm of some Graminese, 

 Diana Bruschi {Ann. [London^, 22 (1908), No. 87, pp. J, 'i9-J,63).— Thin 

 paper, which is an abstract of several preceding papers by the author, gives 

 briefly accounts of experiments with maize, barley, wheat, and rye, which indi- 

 cate that the starch endosperm of the grains investigated can digest itself in 

 the absence of the scutellum and other parts of the embryo, although in differ- 

 ent degrees. The self-emptying of the cells can go on in the absence of any 

 vitality in the amyliferous cells, because the starch hydrolysis is accelerated by 

 a strong amylase which arises, little by little, from a i)ro-enzym existing in the 

 endosperm of the resting seed. This becomes active even though every trace of 

 vitality has been removed from the entire endosperm or seed by mechanical 

 means. The investigations further indicate that vitality is i)ossessed by the 

 aleurone cells situated in the periphery of the endosperm, and it is also retained 

 in one or several subaleuronic layers whence it lessens by degrees mitil it 

 disappears toward the middle of the endosperm, as well as in the part near 

 the scutellum. 



The influence of the concentration of sugar solutions on respiration, 

 A. Maige and G. Nicolas {Coinpt. Rend. Acad. ScL [Paris], 1J,7 (1908). No. 2, 

 pp. 139-142). — Investigations were made on the effect of various concentrations 

 of glucose, levulose, saccharose, maltose, and lactose on the respiration of young 

 bean seedlings deprived of their cotyledons and of etiolated seedlings of broad 

 beans. The normal respiration was determined by the quantity of oxygen ob- 

 served, and the intramolecular respiration by the carbon dioxid given off by the 

 jilants. 



The intensity of the normal respiration was found to increase with the in- 

 creased concentration of all the sugars, except for lactose. Where this form 

 of sugar was used, there was a gradual increase in the respiration activity up 

 to a concentration of 1 per cent, after which the intensity of the respiration 



