ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 161 



modern origin of this species. The writer condudes that the " Taxineas 

 represent a modern group of conifers, as shown by the gradual reduction 

 and final passing out of resin-parenchyma in the more progressive 

 organs." S. G-. 



General. 



Relative Number of Male and Female Plants in Rumex. — 



C. RaunkIuER {Kgl. Danske Vidensk. Selslcah. Biol. Medd., 1918, 1, 7, 

 1-17, 7 tables) publishes the results of further investigations as to the 

 relative number of male and female plants in Rumex. A previous paper 

 dealt with observations made in connexion with R. acetosa, while the 

 present work deals with R. thyrsifiorus. In this species the percentage 

 of female plants is considerably higher than that of male plants, and 

 usually varies between 70 and 95 p.c. This difference is partly accounted 

 for by the inclusion in the species of a primary species or race which 

 gives rise to races which are relatively poor in female plants, or vice versa ; 

 so that it is not unusual for the offspring to vary considerably from the 

 parent-plant in this respect. When the female plants are more abun- 

 dant the male plants are relatively late in flowering. Fertilization within 

 this primary species appears to have poorer results than when different 

 stocks are crossed. S. Gr. 



CRYPTOGAMS. 



Pteridopliyta. 



Apospory in Pteris sulcata L. — "VY. N. Steil {Bot. Gaz., 1919, 

 67, 469-82, 2 pis.). A brief recapitulation of previous work on 

 Apospory, followed by an account of the author's own investigations, 

 which give the following results : — The gametophyte of Pteris sulcata 

 arises normally from a spore, and the embryo sporophyte is of apogamous 

 origin. But under certain conditions the gametophyte was produced 

 aposporously. The gametophytes were formed in connexion with the 

 lamina or petiole of the primary leaf, the line of demarcation being 

 sharply drawn between the cells of the gametophyte and the sporophyte. 

 The prothallial portions developed antheridia, secondary prothallia, and 

 in one case a sporophyte-like outgrowth. The antherozoids were actively 

 motile and normal in appearance. Occasionally forms intermediate in 

 character between gametophyte and sporophyte were formed. The 

 origin of the aposporously produced gametophyte may probably be traced 

 to an early stage in the development of the embryo. Since the embryo, 

 on account of its apogamous origin, is intimately connected with the 

 protliallium, it is not impossible that in some way cells of the prothallium 

 may be embodied in the developing embryo. These cells, retaining the 

 power to divide, may produce such outgrowths as described in the paper. 



A. G. 



Protomarattia, a New Genus of Marattiacese, and Archangiopteris. 

 — BuNzo Hayata {Bot. Gaz., 1919, 67, 84-92, 1 pi., 3 figs.). A 

 description of a new fern-genus, Protomarattia, with one species, 

 P. to?iM)wisis, found by the author on Mt. Tamdao iii the centre 



