906 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



arrowroot of Maranta, and that of the Yams and Sweet Potato. It is a 

 useful contribution to economic botany. — M. C. C. 



Statoliths in Cucurbitaceae, On the Distribution of. By Miss 

 D. F. M. Pertz (Ann. Bot. xviii. Oct. 1904, pp. 653-654). — A note as to 

 the presence of scattered starch and falling starch in various Cucibrbitacea. 

 The results do not conform exactly with those of Tondera. — A. D. C. 



Stellaria nemorum," The Formation of Hibernaeula in. By 



F. W. Neges (Flora, xciii. 1904, pp. 160-163 ; 1 cut).— This species emits 

 from the lower nodes long suckers with small reflexed leaves and elongated 

 internodes, which hang down the rocks and in the autumn penetrate and 

 branch into sods of moss or damp earth. These branches are richly 

 rooted, with crowded subsessile leaves, elongated and fleshy, recalling 

 those of a Cerastium. The runners appear to be neither geotropic nor 

 heliotropic (-f- or — ), but simply hydrotropic. They serve to extend the 

 distribution of the species. — M. H. 



Stigmarian Rootlets, The Vascular Supply of. By F. E. Weiss 

 (Ann. Bot. xviii. Jan. 1904, pp. 180-181). — A supplementary note to the 

 author's paper on Stigmarian Rootlets which appeared in Ann. Bot. 1902. 

 Since then another slide has been obtained showing the vascular supply to 

 form a complete network in the outer cortex. — A. D. C. 



Stomata, A Self-recording 1 Method applied to the Move- 

 ments of. By F. Darwin (Bot. Gaz. xxxvii. No. 2, p. 81 ; with 15 figs.). — 

 The experiments were recorded by means of a Callendar's recorder, a 

 platinum or resistance thermometer, in which the difference between the 

 temperatures of two fine platinum wires is recorded on a revolving drum. 



A leaf with stomata shut is as a rule warmer than one when they are 

 open, as the cooling effect of transpiration acts on the leaf. After 

 describing the process the author discusses the effect of withering. The 

 first effect of severing the leaves is an opening of the stomata, followed by 

 their gradual closing. The cutting off the leaf is accompanied by a 

 practically instantaneous fall of temperature. The effect of dry air was next 

 considered. The closing of stomata, according to Stahl, is due to the loss 

 of water by the guard-cells. Mr. Darwin thinks they do so " in response 

 to a stimulus," possibly "the slight flaccidity of the rest of the leaf." 

 Aloi observed that leaves exposed to a very dry atmosphere may have 

 widely open stomata if the plants are well watered. From his experi- 

 ments it appears that " the closure of the stomata depends on the loss of 

 water in the plant as a whole being greater than the intake." 



This is corroborated by compressing a stem, when " the checked water 

 supply produces closure of the stomata." — G. H. 



Strawberry, Hautbois, Cropping- of. By F. M. (Gard. Ohron. 

 No. 919, p. 85, August 6, 1904). — This paper is a summary of one by 

 Prof. E. Zacharias, in the " Proceedings " of the Natural History Society of 

 Hamburg, 1903, detailing some experiments made by the author to prove 

 the truth of the opinion, prevalent among growers of the " Hautbois 

 Strawberry," that the variety has degenerated owing to long cultivation. 



