322 BOTANY. 



bodies to which the name of starkebilduer' is given, from which starch 

 may be formed as well as from chlorophyl grains. 



The germination of Welwitsehia has been observed by Bower. Dr. 

 Engelmann, in the Trans. Saint Louis Academy, has some notes on the 

 Germination of Acorns, and in the Bot. Gazette, on the Vitality of the 

 seeds of serotinous cones. Prof. Sargent also discusses in the Gazette the 

 Vitality of the Seeds of Pinus contorta. The Am. Naturalist contains 

 papers by Professor Bessey, on the supposed JDimorpMsni of Lithosjjer- 

 mum lonrjiforum, and by Professor Todd ou the Flowering of Saxifraga 

 tomentosa. Meehan, in the Proc. Am. Acad, of Philadelphia, calls atten- 

 tion to the Disarticulacing branches in Ampelopsis. 



Two papers by Goibel should be mentioned : one oi) the Morphology 

 of the Leaf and the other on Dorsiventral Growth, of which a large 

 number of instances are given. The Arbeiten des Botanischen lusti- 

 tuts, Wiirzburg, contains a number of important papers on physiology : 

 Sachs ou Material and Form of Plant Organs ; Elfviug on Some Hori- 

 zontally growing Ehizomata ; Wortmann on the Relations of the Intra- 

 molecidar to Normal Respiration in Plants ; and by Francis Darwin ou 

 the Growth of negative heliotropic Roots in Light and in Darkness. The 

 Influence of the Birection and Strength of the Illumination on some Forms 

 of Motion in Plants, is the title of a paper by Stahl, in the Bot. Zeitung. 

 Species of Mesocarpus according to Stahl are especially instructive, as 

 in this genus the band of chlorophyl rotates so that by strong illumina- 

 tion it lies in the direction of the light ; by weak illumination at right 

 angles to it. Stahl also describes the change of position of chlorophyl 

 grains in cells depending on variations in the illumination. Schweu- 

 dener has studied the subject of several-celled scheitels, and thinks that 

 although such scheitels exist, they are always composed of fewer cells 

 than has been generally believed, and in the case of Marratia, he differs 

 with Russow in only recognizing the existence of four cells. 



BACTERIA. 



It is only possible to enumerate in this connection comparatively 

 few works having a botanical bearing, the majority of the papers on 

 bacteria bei ag more directly concerned with pathological or chemical 

 questions. The Beitrage zur Biologic contains a paper by Neelsen, 

 called Studies on Blue Millt, in which the writer gi\'e3 the results of 

 careful investigations ou the cause of the blue color which is some- 

 times found in milk. He examined milk which had become blue spon- 

 taneously, and was able to produce the color in healthy milk by a pro- 

 cess of inoculation, and ascertain by experiment the conditions wliich 

 favored or retarded the production of the blue color. Of external 

 conditions favoring the i)roduction of blue milk the light has no in- 

 fluence, and the temperature within moderate limits has only a slight 

 influence. On the other hand, the presence of free oxygen and atmos- 



