279 



mens on which it is based were collected by Dr. A. Rehmann in 

 Natal and the Transvaal, South Africa. 



Psoralea esctdenia. Dr. T. F. Wilcox, U. S. A., sending 

 specimens of the " Pomme Blanche " states that it is known about 

 Ft. Niobrara, Neb., as " Bread-root," "Tim-chilla" and "Indian 



Tu 



rnip. 



>> 



Reviews of Foreign Literature 



of the vittcE in the fruit of Umbellife 



t> 



In several numbers of the Bot Zeitung for May and June is 

 a series of short papers by Arthur Meyer on the origin of the 

 partition walls which occur in the intercellular spaces of the fruit 

 of the Umbelliferae. These cavities are technically known as 

 vitt^ and contain the volatile oil which dves the aromatic flavor 

 to many fruits of this order. 



It has been noticed by other investigators that these oil cavi- 

 ties were lined by a certain substance, which in some cases has 

 continued through the cavities in the form of partition walls. As 

 the intercellular spaces are not supposed to contain protoplasm, 

 out of which walls may be built in the regular normal manner, 

 the author has undertaken to determine the origin and function 

 of the walls peculiar to these passages. He first gives the mor- 

 phology and chemistry of the wall as found in ripe fruits. In 

 nearly all cases besides that lining the cavity, partition walls occur. 

 These differ in form and shape in different species. As to their 

 chemical nature, the results of the tests made incline one very 

 strongly to the opinion that they are mainly formed of suberin. 

 The development of the wail is followed from the moment when 

 the secretions from the walls surrounding the cavity are given 

 off in the form of a watery fluid together with tiny oil drops, to 

 the formation of the perfect wall. This watery fluid, he claims, 

 IS the foundation of the wall, and that it differs entirely from 

 protoplasm ; or as he puts it, from cytoplasma as used by Stras- 

 burger. That is, protoplasm without nucleus or chromatophores. 

 Special emphasis is laid on this point, as various other writers 

 are inclined to consider this secretion as protoplasm which has 

 penetrated the walls and found its way into the intercellular spaces, 

 Jn the same manner in which the fine threads of protoplasm con- 

 tmue from cell to cell. Among these authors are mentioned Ber- 



