322 BOTANY. 



bodies to which the name of starkehilducr is giveu, from which starch 

 may be formed as well as from chlorophyl grains. 



The germination of WelwitscJiia 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 Dimorphism of Lithosper- 

 mum lontjiflorum, and by Professor Todd on the Flowering of Saxifraga 

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

 tion to the Disarticulacing branches in Ampelopsis. 



Two i)apers by Goebel should be mentioned : one on the Morphology 

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

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

 tuts, Wiirzburg, contains a number of imi)ortant i^apers on i)hysiology : 

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

 zontally growing Rhizomata ; AVortmann on the Relations of the Intra- 

 molecular to Normal Respiration' in Plants ; and by Francis Darwin on 

 the Groicth of negative heliotropic Roots in Light and in JJarlmess. The 

 Influen<;e of the Direction and Strength of the Illumination on some Forms 

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

 Species of Mesocarpus according to Stahl are esi)ecially 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. Schwen- 

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

 although such scheitels exist, they are always comi)osed 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 being more directly concerned with pathological or chemical 

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

 called Studies on Blue Milk, in which the writer gives the results of 

 careful investigations on 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 which 

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

 conditions favoring the production 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- 



