i9i 2] CURRENT LITERATURE 263 



the seed in January, and by the destruction of the seedlings by spraying with 

 a 10 per cent kerosene emulsion. 



The study of the morphology of the reproductive organs shows a single 

 archesporial cell giving rise to a parietal cell, which Billings says does not 

 appear in T. usneoides. In four or five days after formation the megaspore 

 mother cell begins the divisions that result in a linear tetrad; an embryo sac 

 of the usual type is produced; double fertilization commonly occurs, and the 

 endosperm develops as free nuclei which eventually line the sac and become 

 separated by walls. The development of the embryo is of the usual Alisma 



characteristic of most monocotyledons. The dispersal of the 



typ 



inteeument 



functioning in attaching the seeds to the substratum, upon which they speedily 

 germinate. Under favorable conditions germination frequently occurs within 

 the capsule before the dispersal of the seed.— Geo. D. Fuller. 



Permeability. — Heretofore the power of various anilin dyes to stain living 

 plant cells has been tested on algae, water plants, root hairs, or thin sections of 

 organs of land plants, a method introduced by the pioneer work of Pfeffer. 

 Kuster 18 conceived that surface cells as used in this method may have different 

 permeability characters from the deeper placed ones, also that cells of land 

 plants may have their permeability characters considerably altered by section- 



ing. 



penetrat 



cells in their natural conditions, Kuster used twigs of some size, or at least 

 whole leaves with petioles. The cut ends were placed in aqueous solutions of 



xyl 



living 



along the xylem strands. A number of anilin dyes that former workers have 

 pronounced incapable of entering living cells Kuster finds by this method to be 

 excellent intravitum stains. He distinguishes carefully between true intra- 

 vitum staining and staining due to injured protoplasm. In many cases cells 

 were not injured by many days' treatment with dyes, and dyes abundantly 

 stored in living cells were not reduced in amount by several days' washing in 

 running water. 



His results furnish much evidence against Overton's lipoid theory of 

 permeability; and in contrast to the results of Ruhland on plant cells and 

 Hober on animal cells, show, with few exceptions, a general parallelism 

 between high diffusibility (non-colloidality) of the aqueous solution of anilin 

 dyes and their ability to penetrate the living cell.— William Crocker. 



Chemical unit-characters in maize-— While all inherited characters are 

 probably referable to chemical relations brought about in the segregations and 

 recombinations of the substance and substances of the germ cells, little atten- 



Jahrb. Wiss. Bot. 50: 261-288. 191 1 



\ufnahme von Anili 



