48 BOTANICAL GAZETIE. 



do not contain true green chlorophyll, such as the Phycochromacese, 

 Diatomacese, Fucaceae and Florideae. Starch and oil appear to be re- 

 serve substances produced by the oxidization of the hypochlorin 

 caused by light, it being the most readily oxidizable constituent of the 

 cell, more so even than chlorophyll itself. 



That the hypochlorin— present in variable quantity in every chloro- 

 phyll grain under normal circumstances — is subject to continual in- 

 crease and decrease, may be proved without difficulty. All compara- 

 tive observations on chlorophyll grains in younger and in older condi- 

 tions, point unmistakably to the conclusion that the collection and 

 increase of the starch enclosed in the ground substance of the chloro- 

 phyll, goes on pari passu with the decrease of the hypochlorin. In 

 dark, the hypochlorin, which does not take any direct part in trans- 

 port of food materials, is more permanent than starch ; and this fact 

 again is in agreement with the conclusion that its transformation in the 

 cell into more highly oxidized bodies is hindered by the increased res- 

 piration in light. 



In the facts here detailed, and the conclusions derived from them, 

 Dr. Pringsheim believes that an entirely new light is thrown on the 

 cause of the well-known fact that assimilation takes place only in those 

 cells of the plant which contain chlorophyll. This substance acts uni- 

 versally as a moderator of respiration by its absorptive influence on 

 light, and hence allows the opposite phenomena of respiration and 

 elimination of carbon dioxide to go on in those cells which contain it. 

 A more detailed account of the experiments and results is promised 

 by the author in a future paper. — Alfred W. Bennett, /// Am,. Nat- 

 uralist. 



PtERIS AQUILINA, VAR CAUDATA, AGAIN. — Since mv nOtC in the GA- 

 ZETTE on the huge specimen of this species sent from Florida, I have 

 received the following note from Mr. White: "In compliance with 

 your request I measured a /'/mV as follows : Stipe 6 ft.; first pair 

 of divisions abortive; second pair 8 ft. from ground, and each divis- 

 ion 5 ft. (making a spread of loft., o. e. d.); third pair, spread 8 ft. 

 and the next pair 6 ft: total height 141^ ft. The primary divisions 

 were 2 ft. apart until the last mentioned pair which were \% ft., 

 making a spread of 6 ft. at a height of 1114 ft. from the ground. 

 Almost aborescent, eh.^" ^ 



It will be seen from this that I probably underestimated the breadth 

 of the specimen which I described, and that the dimensions of the 

 specimens measured by Mr. White exceed anything heretofore re- 

 corded anywhere.— Geo. E. Davenport. 



American Monthly Microscopical Journal.— This a continua- 

 tion of the Quarterly and is worthy the support of all interested in the 

 work of the microscope. It is a journal of 20 pages, is illustrated, 

 and costs but one dollar per year. The name of the editor, Romyn 

 Hitchcock, gives an assurance of careful. con.scientious work. 



