86 BOTANICAL GAZETTE [july 



gametophores from protonemata produced by spores, as well as those from 

 secondary protonemata rising from the stem, leaves, and even from the wall 

 cells of antheridia and archegonia, are always bisexual, and the sex characters 

 are not separated until the last division of the spermatogenous and the oogenous 

 cells. The sex characters are united by fertilization and not separated in the 

 tetrad. Therefore in dioicous mosses the sex characters are separate in the 

 spores, protonemata, gametophores, sperms, and eggs, but not in the sporo- 

 phyte ; in synoicous mosses the sex characters are separate only in the egg and 

 sperm. 



Marchal is able to induce apospory in the capsule of Bryum caespiticiutn. 

 Gametophores rising from an aposporous protonema are always synoicous, but 

 the eggs are never fertilized. He concludes that dioicous mosses which have 

 become synoicous through apospory are irremediably sterile. In the synoicous 

 Amblystegium serpens apospory was also induced, and the resulting game to- 

 phores produced eggs capable of being fertilized. In the 4X sporophytes from 

 these fertilized eggs, apospory was again induced, but the 4X leafy shoots, 

 although exceptionally vigorous, have as yet remained persistently sterile. The 

 same results were obtained in other synoicous species, Amblystegium subtile, 

 Barbula muralis, and many others which the author does not name. He states 

 that Ephemerum serratum and Funaria hygrometrica are synoicous. Miss 

 Speer, working in the Hull Botanical Laboratory, first showed that the latter 

 species is occasionally synoicous. Marchal is at present studying a sterile 

 synoicous Bryum atropurpureum which he believes is a natural aposporous 

 derivative of the common dioicous form. 



There are no illustrations, and no definite information as to how the 

 presence of 2X and 4X numbers in the aposporous derivatives were proved; nor 

 are the methods for inducing apospory and for continuing the cultures given in 

 detail. It is an admirable piece of much-needed research, but the lack of a 

 definite and detailed statement of methods is a very unfortunate omission? 

 since many investigators look with suspicion on the work of those who are 

 secretive as to methods when fundamental problems are concerned. — W. J. G. 



Land. 



Phytomyxaceae. — Schwartz, who has recently made several contribu- 

 tions to our knowledge of the parasitic slime molds, gives an account 28 

 of another form which he found on the roots of Poa annua and other grasses. 

 The organism, to which he gives the name Soros phaera graminis without, 

 however, adding a formal diagnosis, is closely related to S. Junci, which the 

 author discovered in the roots of sedges. The organism was found most 

 abundant on plants whose roots were hypertrophied by eehvorms. It is not 

 usually found, however, in the swollen parts, nor does the organism itself 

 produce any form of hypertrophy. The life-history of S. graminis does not 



28 Schwartz, E. J., The life-history and cytology of Sorophaera graminis. Ann. 

 Botany 23:792-797. 1911. 



