482 RECORD OF SCIENCE FOR 1887 AND 1888. 



teria. Little stress was placed by Hellriegel on the observations of 

 Frank, but as Ward has sliown in his paper " on the tubercular swell- 

 ings on the root of Vicia Faba" (Phil. Trans., 1887), there is a clear rela- 

 tion between the presence of this fungus and the power of fixing pure 

 nitrogen, enjoyed by Leguminous plants. A further contribution to 

 the same subject is given by Lawes and Gilbert in Proc. Roy. Soc. 



XLIII. 



" The Comparative Chemistry of Higher and Lower Plants," by Miss 

 Abbott (Am. Nat., xxi), is a very suggestive paper, although still lack- 

 ing confirmation in many particulars. It is claimed by the author that 

 a progression in chemical complexity can be traced pari passu with 

 the progression in structural differentiation. Of the other jiapers of 

 more or less interest may be mentioned the following: Staco, " Plant 

 Odors" (Bot. Gaz., xii); Schimper, " Ueber Kalkoxalatbildung in den 

 LaubbUittern" (Bot. Zeit. 46 Jahrg). 



Krasser, " Ueber den microchemiochen nachweis von Eiweiss korperu 

 in den Pflanzlichen Zellhaut" (Bot. Zeit 46); "On the Nature and 

 Toxic Principle of the AroidcT," by Pedder and Warden (Journ. Asi- 

 atic Soc. Bengal, lvii). The authors here found that the irritating effect 

 on tongue, stomach, etc., of the Aroidew is a purely mechanical one. 

 The cells of the Arums are filled with needle-shaped crystals of oxa- 

 late of lime and by mechanical action produce the deleterious effects; 

 " The AsU of Tillaudsia usneoides, by Palmer (Am. Nat. xx). 



TECHNOLOCtY. 



The constantly increasing attention that is being given to the micro- 

 scopical study of plants has given rise to a copious literature of the 

 subject, which has been considerably added to during the year. Det- 

 iner's "Das Pflanzenphysiologische Praktikum" is perhaps the most 

 imjiortant work that has appeared. The work is evidently the result 

 of the author's i)ersonal experience in teaching physiology, and is a 

 very carefully written account of all the manipuhitions required to 

 illustrate the ordinary facts of plant physiology. The details are very 

 minutely given. " Manipulations de Botanique, guelle pour les travaux 

 d histologic vegetale," by Girod, is also a valuable work. "The appli- 

 cation of the paraffin — imbedding method in Botany," by Moll (Bot. 

 Gaz., XIII), is a very interesting paper detailing accounts of the sucess- 

 ful imbedding and cutting of the most delicate vegetable tissues, such 

 as the growing point of roots and stems, flower buds, etc. The appli- 

 cation of zoological methods to botany has only recently been success- 

 ful, since the last edition of Strasburger's " Botauische Praktikum" 

 contains no mention of it. Schonland has also contributed observations 

 on the process of imbedding (Bot. Centralbl, xxx, and Bot. Gaz., xiii), 

 and Campbell also has a short note in Bot. Gaz., xiii. Bumpus has 

 described (Bot. Gaz., xii) a simple and inexpensive self-registering aux:- 



