NOTES AND ABSTRACTS. 



171 



the sand together, such as dandehon, the greater Plantain, Hieracium 

 aurantiacum and H. pilosella. Kidney Vetch, Sainfoin, Sickle Medick 

 and Meiilot. Bromus inermis, Agrostis maritima, Vernal grass and Sea 

 Matweed also do well. They should not be mown the first year after 

 sowing. Dwarf Sedum and Saxifrages, Pyretlirum Tchihatchewii, 

 Chicory, Ononis spinosa and Scahiosa canescens may also be added with 

 good effect.— 5. E. W. 



Sap, Ascent of. By J. B. Overton {Bot. Gaz. pp. 28-63, Jan. 

 1911; 1 fig.)- — Gives a very full historical resum4 of the papers 

 dealing with the question of how far living cells in the stem assist 

 in the raising of sap. His own experiments were carried on with 

 Cyperus alternifolius. He found that when portions of the stem 

 were killed by steam or by bot paraffin wax, the rate of transpiration 

 was much reduced, and eventually the leaves withered. 



But from the length of time necessary to produce withering and 

 from appearances in the stem, he is inclined to consider that the 

 check in transpiration may be due to disorganized substances clogging 

 the vessels. In wax-killed stems where no such materials were seen, 

 withering was much more gradual. — G. F. S. E. 



Saprophytes of Java, Contributions to our Knowledge of. 



By A. Ernst and 0. Bernard {Ann. Jard. Bot. Butt. ser. ii. vol. ix. 

 pt. i. pp. 65-77, 1911; with 6 plates). — Part iv. of these contribu- 

 tions is from the pen of J. J. Smith, and deals with the systematic 

 description and bibliography of Thismia clandestina and T. Ver- 

 steegii. Part v. (by Bernard and Ernst) describes the anatomy of 

 these two species. It is pointed out that the roots of these plants 

 possess a normal root-cap which takes its origin from an initial 

 layer which is common to the root-cap and the epidermis. The outer 

 region of the cortex contains one (in T. clandestina) or two (in T. 

 Versteegii) layers of cells occupied by the symbiotic fungus. The 

 older roots appear to contain no true starch. The leaves of these 

 plants are simple in structure, and possess no stomata on either 



' the lower or upper surface. 



Part vi. (by Bernard and Ernst) describes the embryology of 

 Thismia clandestina and T. Versteegii. Although a complete series 



I was not obtained, many of the more important stages of develop- 

 ment were followed. The egg-apparatus and polar nuclei appear in 



I the usual way; the antipodal cells are only feebly developed. The 

 nucellar tissue, completely surrounding the embryo sac in the earlier 



j stages, disappears laterally at a later period, and only remains as two 



• caps over the ends of the sac. In T. clandestina (and probably also 

 in T. Versteegii) the endosperm cells contain starch during the early 



I stages of development, but this disappears later, and the reserve 

 carbohydrate is stored in the greatly thickened cellulose walls of the 

 : I endosperm. Two cells at the base of the endosperm in both species 



I of Thismia are differentiated from the rest, and might easily be 



I mistaken for antipodal cells. The embryo contained in the seed of 



i 



