AGRICULTURAL BOTANY. 633 



S5 (idfS), No. B 578, pp. 2 1 Jt-2 18).— Studies were made of the distribution of 

 oxidases in connection with the formation of pigments in the Chinese primrose 

 ( Pnmula sinensis ) . 



The distribution of pigment in tlie flower was found to coincide with that 

 of peroxidases, two of which were found in the primrose, one occurring in tlie 

 epidermis and in some cases in the layers subjacent to the epidermis, while the 

 other was localized in layers of cells neighboring the woody tissues of the vas- 

 cular bundles. The epidermal and bundle peroxidases were found to differ 

 from one another both in their distribution and in their color reactions. Cer- 

 tain varieties of the Chinese primrose give under certain circumstances a direct 

 oxidase reaction. The bundle peroxidase of the iietals of the flower is located 

 in the cells of the bundle sheath which surrounds the veins. 



White flowers which are known to be dominant whites are said to fail to give 

 the epidermal peroxidase reaction, but in such flowers a faint bundle peroxi- 

 dase reaction may occur. Both epidermal and bundle f)ej'oxidases are, however, 

 present in dominant white flowers, the white primulas containing a substance 

 which inhibits but does not destroy the pigment-producing peroxidase. 



Observations made on the epidermal and bundle peroxidases are believed to 

 throw light on the significance of sporting in cultivated flowers, the authors 

 being inclined to regard flaking as the effect of the bundle peroxidase on the 

 chromogen-containing cells neighboring on the bundle sheath. The white color 

 is attributed to an inhibitor associated with and nullifying the epidermal 

 peroxidase. The marked localization of pigmentation effected by bundle peroxi- 

 dase appears to be due to anatomical causes, such as the degree of development 

 of the cells and the nearness of the veins to one another. 



The existence of two localized peroxidases which may induce pigmentation and 

 may reenforce one another along certain tracts of tissue is held to provide 

 material facts for the explanation of color range and color pattern in flowers. 



The occurrence of urease in higher plants, G. Zempl£n (Eoppe-Seyler's 

 Ztschr. Phijsiol. Chem., 79 (1912), No. 3, pp. 229-234; «6s- in Jour. Chem. Soc. 

 [London], 102 {1912), No. 597, II, p. 67//).— In a series of investigations to 

 ascertain the presence and proportion of urease in certain agricultural plants, 

 the author found it in a large number of the Papilionacese, different species of 

 which contain this enzym in widely varying percentages, while in the Grami- 

 nete it was present, if at all, in quantities scarcely demonstrable in most cases. 

 Tabulated details are given and an early discussion is promised. 



The action of bisulphid of carbon on the germination of seeds, B. FiNzi 

 {Stas. Sper. Agr. Ital., U {1911), No. 11-12, pp. S-'/3-S^8).— A preliminary note 

 by the author on his experiments shows that exposure to carbon bisulphid vapor 

 during periods varying from 30 minutes to 48 hours accelerated the germination 

 of seeds of /Egilops cylindrica, Bromns erect us, Trigonella fwrnim grwcum, 

 Paniciim miliaceiim, Canna cupheana, and C. orientalis. The seeds of 8 other 

 species either showed little or no acceleration or appeared to be retarded. 



Nutritive chang'es in sprouting pumpkin seeds, F. T. Pebituein {Isv. 

 Moskor. Selsk. Khoz. Inst. {Ann. Inst. Agron. Moscou), 18 {1912), No. 2, pp. 

 228-256). — The pumpkin seeds experimented uix)n were divided into 4 lots and 

 sprouted in water and in solutions of ammonium chlorid, ammonium chlorid 

 with calcium carbonate, and ammonium chlorid with calcium sulphate. After 

 10 days the seedlings were analyzed and the fat and nitrogen contents ascer- 

 tained. The results are given in tabular form. It appears therefrom that 

 etiolated seedlings take up ammonia not as such but as asparagin, the larger 

 results being obtained v>"hen the calcium salts were employed with ammonium 

 salt in the nutritive solutions. 



