ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 671 



maximum development is not obtained by the lowest leaves on a 

 branch, but by those on the middlemost nodes ; on a branch containing 

 sixteen leaves by those from the seventh to the eleventh, the lowest 

 showing less than half the maximum power of production. 



If an annular incision is made above and below a leaf, separating 

 the elements of the soft bast, the starch in the leaf is not absorbed 

 and transformed in the dark ; but if a similar incision is made only 

 below or only above the leaf, the ordinary process is not disturbed ; 

 and this is also the case if a leaf separated by an incision on both 

 sides has a panicle of fruit or flowers opposite it on the same node. 

 No starch is formed if the leaves are etiolated or attacked by Perono- 

 spora viticola. 



Starch in Vessels.* — Dr. A. Fischer records the abnormal occur- 

 rence of starch in vessels in the leaves of Plantago major. He found 

 them only in the vessels of the leaf-stalk, not in those of the veins of 

 the leaf itself, and mostly only in the spiral vessels of the stronger 

 bundles. Portions of these vessels were filled with starch-grains, 

 while in other parts they were entirely wanting. 



Presence of Manganese in Plantf.j — According to M. E. J. 

 Maumene, manganese occurs in small quantities in most vegetables. 

 Tea is particularly rich in manganese, from • 5 to • 6 p. c. ; so also 

 is tobacco, especially the Kentucky variety, which contains from 1 • 5 

 to 1 • 6 p. c. Both yellow and red cinchona bark appear to contain 

 more than traces of manganese. 



Nutritive Properties of the various portions of the Grain of 

 "Wheat.J — M. A. Girard states that of the three parts of which the 

 grain of wheat may be said to consist, viz. (1) the integument, in- 

 cluding the outer envelope of the endosperm, (2) the endosperm, 

 and (3) the embryo, the value for nutritive purposes resides almost ex- 

 clusively in the second. Both the integument and the embryo contain 

 a considerable proportion of nitrogenous substance ; but this is chiefly 

 in the form of cerealin, a substance almost valueless for nutritive 

 purposes from its insolubility. Its fermenting properties render 

 cerealin absolutely injurious in the making of bread. The embryo 

 contains in addition an easily oxidizablc oil, which has a very pro- 

 judicial effect in promoting the rapid decomposition of the bread. 



Assimilating Cavities in the interior of Tubers of Bolbo- 

 phyllum.§ — Prof. E. Pfitzer describes the structure of the remark- 

 able Bolbophyllum minutisdmum, from Port Jackson, one of the 

 minutest flowering plants. One of the most remarkable features is 

 the occurrence in the disk-shaped tubers of peculiar chambers opening 

 out into the external air only by a narrow cleft, the epidermal layer 



• Bot. Ztg., xliii. (1885) pp. 89-95, 



t Bull. 8oc. Chim., xlii. jip. 305-15. See Journ. Chem. Soc— Abstr., xlviii. 

 (188.5) p. 421. 



X Ann. Chim. ct Pliys., iii. (1884) p. 289. See Niiturforschcr, xvlii. (1885) 

 p. 44. 



§ Bcr. DcutBch, Bot. GcbcU., ii. (1885) pp. 472-80 (I pi). 



