Physiologie. 697 



stances hj^drocarbonnees, mais aussi dans les transformations 

 chimiques ulterieures de ces substances, dans le tissu vegetal. Les 

 Sucres accumules dans le tissu chlorophyllien par l'activite des chlo- 

 roleucites se transforment ensuite en cellulose, en glucosides et 

 d'autres substances, que la plante utilise pour la construction de 

 ses tissus et des nouveaux organes; ces memes Sucres donnent 

 aussi naissance aux divers produits de desassimilation, tels que les 

 huiles essentielles. Et la plante utilise l'energie lumineuse aussi 

 pour ces nombreuses transformations des Sucres elabores. Les 

 experiences des auteurs montrent que c'est l'intensite de la lumiere 

 qui determine la marche des reactions chimiques dans ce cas ainsi 

 que Taccumulation preponderante de certains produits provenanls 

 des Sucres. M. J. Sirks (Haarlem). 



Moore, B, The presence of inorganic iron Compounds 

 in the chloroplasts of the green cells ofplants consi- 

 dered in relationship to natural photosynthesis and 

 the origin of life. (Proc. Roy. Soc. Lond. LXXXVII. B. p. 

 556-570. 1914.) 



According to the author, iron salts are present in the colour- 

 less portion of chloroplasts, and it is suggested that these colloidal 

 iron Compounds are effective in bringing about the formation from 

 carbon dioxide and water of the simple carbohydraies which are 

 the first products of photosynthesis. F. Cavers. 



Pearson, H. H. W., Observations on the internal tempe- 

 ratures of Euphorbia virosa and Aloe dichotonia. (Ahn. Bolus 

 Herbarium. I. 2. p. 41-66. 1914.) 



The observations on the above mentioned plants were made at 

 4200 ft s. m., on the western flanks of the Great Karasberg Range 

 in Great Namaqualand. In the first place the anatomy of the 

 two stems, respectively is dealt with briefly, mainly with regard to 

 the air cavities in each. The author in summarising states that „the 

 Euphorbia responds more quickly than the Aloe to changes in the 

 external temperature-conditions and attains higher maxima. In each 

 case the internal temperature begins to rise very slowly a few mi- 

 nutes before the plant is touched by the rising sun; when fuUj'' 

 illuminated the temperature rises much more rapidly, tili in the 

 case of the Euphorbia a maximum temperature is reached 2 p. m. 

 on unclouded days. The temperature of the Aloe 5tem continues to 

 rise for some hours after the meteorological maxima are past." 

 Many Charts are given, on which the maxima and daily ranges are 

 tabulated. The effect of wounding has also been investigated in the 

 two plants. In both a fall of temperature foUowed the wound, — 

 the rapid recovery in temperature of the Euphorbia and the ver}- 

 slow recovery in the Aloe being probably due, mainly or entirei}', 

 to the fact that the wound is sealed by coagulated latex in the for- 

 mer and not in the iatter. E. M. Tesson (Kew). 



Raynep, M. C, Obligate Symbiosis in Calluna vulgaris. {Ann. 

 of Botany. XXIX. N" 113. p. 99-133. 4 figs. and 1 doub. plate. 

 1915.) 



In a previous paper (Bot. Cbl. CXXIII p. 280) it was shown 



