584 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Gemmse of Aulacomnion palustre.* — This moss was found in 

 1882 growing in the propagating pits at Kew, where it flourished 

 without, however, showing any trace of sexual organs. F. O. 

 Bower finds that ordinary vegetative axes often bear towards their 

 apices structures of a foliar nature, and show a special adaptation 

 for effecting the asexual or vegetative reproduction of the plant. On 

 passing upwards along one of these axes or pseudopodia, there is 

 found a gradual transition from the normal leaf to the leaf-gemma3, 

 which are readily removed from the plant by a slight mechanical dis- 

 turbance, and are then capable of immediate germination when laid 

 on damp soil or floating in water. 



Relation between Increase and Segmentation of Cells.j — Prof. 

 Beketoff criticizes Sachs' theory as to the relations between the 

 increase and segmentation of cells in the embryonal parts of plants. 

 While he warns one against the application of geometrical theories to 

 botany, he points out how some of the conclusions arrived at by 

 Sachs could be more easily explained by the principles established by 

 Hofmeister. 



Development of Starch-grains in the Laticiferous Cells of the 

 Euphorbiacese.l — The development of the starch-grains in the latici- 

 ferous cells of the Euphorbiace^ is described by M. C. Potter as 

 taking place in the interior of rod- or spindle-shaped starch-forming 

 corpuscles which lie in the parietal protoplasm of the cell. 



The starch-grain is at first visible, through the agency of iodine, as 

 a thin streak in the interior of the starch-forming corpuscle. This 

 streak, through the deposition of starch, assumes a rod- or spindle- 

 shape ; it increases in length and breadth, the starch-forming corpuscle 

 at the same time increasing. When the starch-grain has attained nearly 

 to its maximum dimensions in length and breadth, the starch-forming 

 corpuscle collects at both ends of the rod-shaped grains, and there 

 forms the masses of starch at the end of the rod, causing it to assume its 

 remarkable shape, resembling a bone. The starch-grains are doubly 

 refractive, but instead of the black or white cross of other starch- 

 grains they show a central black (or white) line surrounded on both 

 sides by white (or black) lines. 



Constitution of Chlorophyll.§ — E. Schunck extracts leaves with 

 boiling alcohol, and after some time filters ; the filtrate is mixed with 

 its own volume of ether and two volumes of water ; it then forms two 

 layers, which are separated. The lower layer is yellow, and reduces 

 Fehling's solution. The upper layer is green, and contains all the 

 chlorophyll ; it is thoroughly washed free from everything soluble in 

 water. When the ether is evaporated the bright green residue, 

 dissolved in alcohol and treated with alcoholic potash, does not reduce 

 Fehling's solution, but if it is previously treated with concentrated 



* Journ. Linn. Soc. Lond.— Bot., xx. (1884) pp. 465-7 (4 figs.), 

 t Mem. Soc. Naturalistes !St. Petersbourg, xiii. See ' Nature,' xxix. (1884) 

 p. 461. 



I Jonrn. Linn. Soc. Lond.— Bot., xx. (1884) pp. 446-.50 (4 figs.). 

 I Proc. Roj-. Soc, xxxvi. (1884) pp. 183-5, 28.5-6. 



