3°6 The Botanical Gazette. [November, 



Ht 



that there is a 



remarkable water-pore at the apex of the leaf, formed by the 

 disintegration of certain epidermal cells. This pore is in 

 communication with the vascular system of the leaf and to- 

 gether with the ordinary stomata on the under surface facili- 

 tates the passage of a current of water through the whole 

 organ. By means of immersing cut-off shoots of Potanwge- 

 ton, etc., imbedded in the ends of bent thistle-tubes contain- 

 ing water and attached to a mercury pressure-guage, in jars 

 of water, Sauvageau demonstrates experimentally the ab- 

 sorption of water by the leaves. He concludes that there are 

 currents of water, comparable to the water-current of trans- 

 piration in land-plants, in the leaves of the Potamogctonaccce, 

 and that, when deprived of their roots, these plants may con- 

 tinue to live and prosper by absorbing water and salt-solu- 

 tions through their leaves. Plasmolytic phenomena noted 

 indicate that in these plants the absorption of water may 

 take place over the whole surface of the leaf. 



In general it may be said that these extremely able and 

 careful investigations of Sauvageau go far to show that ab- 

 sorption of water is, in some cases, an " important normal 

 function " of leaves. This has not yet been entirely clear, 

 notwithstanding the well-known experiments of Mayer and 



Boussmgault. —Conway MacMillan. 



Structure of living protoplasm. 



Probably the recent article by M. Fayod 1 upon this sub- 

 ject is as startling and difficult to reconcile with preconceived 

 and accepted notions, as any physiological memoir that has 

 appeared since the early days of karyokinesis literature. M. 

 t-'ayod announces that protoplasm is not an emulsion, as it 



Q 



it a zoogioea-hke by-product enclosing bacterioid scll-granu- 

 m, as the Harttgs have indicated, nor a "complicated mix- 

 ture as Berthold somewhat indefinitely calls it. It is, on 

 tne contrary, a highly intricate network of spirally twisted, 

 n J*?t \~ ft h ° l0W fibriIlai > each possessing a hyaline wall 

 b -Th r f Staming rea ^ ents and capable of great dilation 

 knot o q T %°7 e ,T ulsi ° ns within - The nucleus is a peculiar 

 knot of sptrofibrtll^ The c ell-wall possesses exactly the 



' Kev. g^nerale de B^T^T^T^^, </;/ protoplasm ^^l. 



