ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 415 



through the cell-walls, but by filtration from cell to cell ; although 

 the former may occur in special circumstances, as, for example, when 

 all the fluid water has been removed from the wood by transpiration. 



Origin and Morphology of Chlorophyll-corpuscles and Allied 

 Bodies.* — F. 0. Bower gives a useful summary and discussion of the 

 results of recent researches on this subject, especially those of 

 Schimper, Meyer, and Schmitz which have already been noted here. 



Under the heading of " the Trophoplasts " A. Meyer also gives | 

 a summary of the results of the recent work on Chlorophyll- 

 corpuscles. 



Spectrum of CMoropliyll.$ — A. Tschirch continues his researches 

 on " pure chlorophyll," the term which he applies to the product 

 obtained by the reduction of chlorophyllan by means of powdered 

 zinc. In the so-called " solid chlorophyll," obtained by evaporating 

 pure chlorophyll in a glass vessel he notices a small displacement of 

 the absorption-bands of the spectrum towards the red as compared 

 with an alcoholic solution ; and the same phenomenon is presented by 

 chlorophyll dissolved and hardened in paraffin. In the solid chloro- 

 phyll of the leaf there is a much greater displacement in the same 

 direction. This results, in the author's opinion, from the chlorophyll- 

 grain being a mixture of two substances, pure chlorophyll and 

 xanthophyll. A useful synonymy is appended of the terms employed 

 by different writers in describing the various members of the chloro- 

 phyll group. 



Portion of the Spectrum that decomposes Carbon Dioxide. § — 



C. Timirjaseff maintains that a solution of chlorophyll is not, as held 

 by Wiesner and others, decomposed most quickly by the yellow, but 

 by the red rays. The decomposition of carbon dioxide, as well as the 

 transformation of chlorophyll, is caused by one and the same group 

 of rays absorbed by the pigment. The green group of rays is not 

 absorbed at all by weak solutions of chlorophyll. 



Chlorophyll in Cuscuta.|| — The parasitic Guscutm have hitherto 

 been described as entirely destitute of chlorophyll. F. Temne, how- 

 ever, finds distinct indications of its presence by C. europcea. This 

 was established by an evident green tinge, either of the whole proto- 

 plasm or of separate granules, especially in the inflorescence ; by 

 the spectrum of chlorophyll obtained in an alcoholic extract; and 

 by direct evidence of the evolution of carbonic acid. 



Work performed by ChlorophylLt — From a series of experiments, 

 C. Timirjaseff deduces the result that, where there is energetic decom- 



* Quart. Journ. Micr. Sci., xxiv. (1884) pp. 237-54 (1 pi.). 



t Biol. Centrabl., iv. (1884) pp. 97-113. 



X Ber. Deutsch. Bot. Gesell,, i. (1883) pp. 462-71 (1 pi.); and ibid., 

 Generalvers. in Freiburg., xvii.-xxii. 



§ Arbeit. St. Petersb. Naturf. Gesell., xiii. (1883) p. 10 (Russian). See Bot. 

 Centralbl., xvii. (1884) p. 101. 



II Ber. Deutsch. Bot. Gesell., i. (1883) pp. 485-6. 



^ Arbeit. St. Petersb. Naturf. Gesell., xiii. (1883) p. 9 (Russian). See Bot. 

 Centralbl., xvii. (1884) p. 100. 



