45 

 FURTHER STUDIES IN PLANT EMBRYOLOGY. 



By Lumina Cotton Riddle, M.Sc. 



Under this title was presented some preliminary 

 work on the development of the macrosporangium of 

 Staphylea tri folia L. Illustrations in india ink were 

 shov\^n of the stages so far studied. Owing to 

 division of the hypodermal cells and numerous 

 divisions of the tapetal cell, the embryo sac which 

 developes from the lowest of the macrospores is very 

 deep seated. This may possibly account for the fact 

 that very few of the numerous ovules ever develop 

 seed. Various stages of the embryo sac were shown, 

 up to the mature form having egg apparatus, de- 

 finitive nucleus and antipodals, perfect. A very pretty 

 bipolar spindle was found in the first division of the 

 macrospore mother cell. 



SOME ABNORMAL PLANT SPECIMENS. 



By Lumina Cotton Riddle, M.Sc 



Frequently, while crossing the University Campus 

 during October ]898, I noted the peculiar bushy heads 

 of the common timothy Phleum pratense L. Nov. Gth, 

 1898, Professor Kellerman brought some in for class 

 work, and. later, I made careful examination of these 



