312 Pteridophyten. — Pflanzenchemie. 



case examined the adaxial (morphologically lateral) protoxylems of 

 each bündle were at first mesarch; in several cases this was true 

 also of the abaxial (morphologically median) groups also though 

 less markedly so. The two bundles of the Onoclea type would, if 

 approximated by their adaxial faces, produce a triangulär mesarch 

 bündle of the type regarded as relatively primitive. The bundles of 

 this type of trace are always close together at their origin and 

 sometimes fused; higher up they pull apart. In some genera 

 {Woodwardia , Aspidium) the Onoclea trace is found in certain spe- 

 cies and a more complex derivative form in others. The Cyatheaceae 

 with their complex traces seem also to be derived from the primi- 

 tivety triangulär triarch type; the author found a triangulär arched 

 bündle in the young Cyalhea Macarthnri, which soon divides into 

 two bundles of the Onoclea t}^pe and later into more numerous 

 Strands. Plagiogyria as investigated by Bower and Pellaea atropur- 

 purea have also traces that are triarch and mesarch at their base. 

 Lindsaya, believed by many to be anatomically very simple, seems 

 to have, as have Odontolonia and Stenoloma, a. reduced trace, for 

 at its origin it is a small diarch elliptical or curved band; in the 

 petiole it becomes triarch but the adaxial hooks are absent. 



Finally the author opposes Tansley's and Gwynne Vaug- 

 han's view that the siphonostele was produced by the influence oi 

 the arched trace on the protostele. The size of the transpiration 

 current can hardly affect the supply of vascular tissue much, as it 

 is accomodated as well by the smaller and simpler bundles of the 

 base of the leaf as by the larger and more complex ones of the 

 petiole. Further how can the Onoclea petiolar sj^stem have caused 

 the widening of the dictyostele since both vascular Systems are 

 contracted where they meet? It would therefore seem that the vas- 

 cular System of stem and petiole have increased in size and com- 

 plexity independentby. The increase in size of the petiole where it 

 becomes free is probably a response to mechanical needs; since 

 the lower part of the petiole is either subterranean or supported 

 by old leaf bases this mechanical need does not usually arise at 

 the very base of the leaf. The conservatism of the leaf trace, parti- 

 cularly at its base, is also emphasized. Isabel Browne (London; 



Yasui, K., On the Life History of Salvinia natans. (Ann. Bot. 

 p. 470-483. PI. 41—43. 1 textfig. April 1911.) 



The somatic number of chromosomes in Salvinia natans is 16,' 

 the number in the cells of the gametophyte is 8. Miss Yasui, un- 

 like Campbell, found that the two groups of sperm cells were 

 always separated by a sterile cell and believes that each group 

 represents an antheridium. In Opposition to Juranyi and Campbell 

 but in agreement with Heinricher she describes the tapetum as 

 one layered. She also finds, with Heinricher, that there are 8 and 

 not 16 sporemother cells. The archegonia, 3—5 in number, have 

 no basal cell; the nucleus of the neck-canal-cell divides. After fer- 

 tilization the embryo divides into quadrants, the root quadrant soon 

 ceasing to function and becoming indistinguishable from the tissue 

 of the foot. Isabel Browne (London). 



Flieringa, J., Ueber das Saponin aus den Blättern von 

 Trevesia snndaica. (Arch. Pharm. CCIL. p. 161. 1911.) 

 Das Rohsaponin wurde durch Aussalzen des mit Wasser ver- 



