294 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



yet been published. Some years since I collected a small 

 amount of material of the flowers of the common eastern 

 species, E. eurycarpum Englm., and an examination of 

 this material revealed several puzzling peculiarities of the 

 embryo-sac, which were not clearly understood at the 

 time. Figures of a few of these were published two 

 years ago (Campbell, 1897), but lack of proper material, as 

 well as other work, prevented any further study at the time. 

 During the summer of 1896 a trip to Japan enabled me to 

 procure a few specimens of the Japanese S. longifolium 

 Turcz., and during the past season a good supply of S . si?u- 

 flex Huds. was collected in August at Tallac on Lake 

 Tahoe. This species proved very satisfactory for study, and 

 was made the principal subject of my investigations. In 

 September, through the kindness of Miss Eastwood, a 

 quantity of S. Greenii Morong. collected at Lake Merced, 

 near San Francisco, was sent me, and served to supplement 

 the work done on S. siiivflex. My material of the latter 

 species was much more complete than that of any of the 

 others, and moreover it proved easier to handle. The 

 results obtained from a study of this species have been 

 compared, so far as was possible, with those from the other 

 species mentioned. 



A preliminary statement in regard to S. simplex has 

 already been published in a recent number of the "Botanical 

 Gazette" (Campbell, 1899); but this refers simply to cer- 

 tain of the most striking points concerning the embryo- 

 sac, and no account of the embryo is included. 



Unfortunately all of the material collected was too old to 

 show the earlier stages of development of the flower, so 

 that the early history of the pollen and embryo-sac could 

 not be traced. In the youngest flowers examined, the 

 structures of the embryo-sac were already complete, and 

 in most cases the embryo-sac was ready for fertilization. 

 Hence in the present paper the study of the flower begins 

 at the time when it is ready for pollination. 



In the preparations of the material, various reagents were 

 employed in fixing it : one-half to one per cent, chromic acid, 



