1902] CURRENT LITERATURE 257 



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of the green nut is an aqueous solution containing large proportions of a 

 reducing sugar (probably a mixture of dextrose and galactose) and some cane 

 sugar, together with much hydrochloric and phosphoric acid in combination 

 with both alkaline and earthy bases. There is very little proteid in either 

 milk or endosperm. In the mature nut the milk contains little monosac- 

 charide and much cane sugar. The mature endosperm contains much fat 

 and insoluble carbohydrate material The fat is mainly glycerides of capry- 

 lic, lauric, myristic, and palmitic acids. Besides cellulose, a polysaccharide 

 gum is present in considerable quantity, and several sugars, but these only in 

 small amount. The proteid present is largely edestin. A diastatic enzyme 

 and oxydase occur in both milk and endosperm, but no appreciable quantities 

 of any protoelytic or adipolytic enzyme were found. — B. E. Livingston. 



Miss Ethel Sargant'7 has long been studying the vascular system in 

 monocotyledonous seedlings, and has reached the conclusion that the sym- 

 metry and structure of the vascular system of the seedling can be used as a 

 guide to the phylogeny of the Liliaceae. She regards the genus Anemar- 

 rhena as a primitive type in the family, two opposed collateral bundles occur- 

 ring in the cotyledon. This is taken to represent the " bicotyledonary *' system 

 of a remote ancestor. In other words, the monocotyledons are specialized,, 

 reduced forms of dicotyledons, in which two separate cotyledons have 

 gradually united. It will be recalled that Mr. H. L, Lyon'^ has suggested on 

 the other hand, that the dicotyledonous condition has been derived from the 

 gradual splitting of the single cotyledon of monocotyledons. Miss Sargant 

 calls attention to the fact that among monocotyledons the apex of the cotyledon 

 often remains within the endosperm, a habit that ''would naturally lead in 

 course of time to the fusion of the cotyledons within the seed." In a later 

 number of the same journal ^^ Mr. A. G. Tansley objects to this *' reduction" 

 theory.— J. M, C. 



George James Peirce^ has studied "The root-tubercles of bur clover 

 {Medicago denticiilata\^\\\^:) 2a\A oi some other leguminous plants." His 

 conclusions are that though the bacteria that form the tubercles are usually 

 only slowly motile in artificial cultures, this proves nothing as to their motility 

 in the soil ; that the proportion of root hairs affected is very small ; that infec- 

 tion of the roots may be resisted by cutting off the infected ends of the root 

 hairs; that the bacteria enter a root hair by softening or dissolving a small 

 portion of the wall and moving or growing through this ; that the infection 

 thread is chemotropically attracted to the layer of cells next the central 

 cylinder; that the tubercules originate only endogenously and from the same 



'7 The origin of the seed-leaf in Monocotyledons. New Phytol. i : lOJ-Hj- 1902. 



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'■Minn. Bot. Studies 643-655. 1901. '^New. Phytol. i : I3i-I33- I902. 



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Proc. Calif. Acad. Sci. III. Bot. 2 : 295-328. //. sq, 1902 



