50 THE BOTANICAL MAGAZINE CVoi. xxxvi. No. 425. 



found to contain three embryos. In some instances the axis of those 

 embryos were quite parallel with one another, but in others one of 

 the embryos would be placed rather obliquely to the other embryos. 

 This divergence was so pronounced in some cases that the scutellum 

 was nearly parallel with the coleorhiza of the adjacent embryos, but 

 otherwise the embryos were found to be perfectly normal in structure 

 and developed into plants that were quite as vigorous as those 

 obtained from the normal grains. 



It is evident that we have here an illustration of the excess sto- 

 rage of reserve materials beyond the requirements of the seedling, for 

 in these instances there was sufficient material to insure normal 

 development of each embryo. The significance of the position and 

 peculiar relations of these embryos will be considered when we come 

 to an examination of fecundation and embryo formation. 



2. Polyembryony. — The low percentage of germination of Poa 

 pratensis as well as the occasional occurrence of polyembryony led 

 me to investigate its reproduction aud embryology. 



The pollen grains showed no departures. They developed and 

 germinated normally. The pistils more commonly were also normal, 

 but occasionally slightly larger than normal ones were found. 

 These were characterized by protuberances (Fig. 4). This type of 

 pistil may be due to the deposit of eggs by an insect, a full account 

 of which phenomenon together with detailed embry ©logical features, is 

 presented in a later report. Other types of protuberances from the 

 ovaries were also noticed leading up to three nearly normal stigmas. 

 Three normal stigmas were also noticed in millet, and have been 

 reported in rice and bamboo. 



We are indebted to Fischer 10 (1880), Norner 24 (1881), True 34 

 (1893), D'hubert 16 (1896), Koernicke 19 (1896), Cannon 3 (1900), 

 Guignard 12-13 (1901), Kuwada 21 (1910) and others for various con- 

 tributions upon the embryology of the Gramineae. I have found no 

 reference to polyembryony in the grasses except that of the recent 

 observation of Komuro (1922) in rice. In germinating some grains of 

 corn in November, 1919, I observed one grain with two normal 

 embryos, each with its coleoptile, scutellum, coleorhiza and root. 



This preliminary report on embryology shows that the course 

 of development may be quite normal embryo. The embryology of 

 Poa pratensis, however, showed frequent instances of polyembryony 

 associated with the development of massive suspensor (Fig. 6). Two 

 and even three buds may develop from the suspensory apparatus. 



