Manchester Memoirs, Vol. Ivii. (1913), No. <). 



3 



Should the former be the case it is probable that the 

 tetraspores are formed without the mother-cell nucleus 

 undergoing meiosis.* In the latter case the egg-cells 

 may possibly develop apogamously, producing a second 

 successive diploid generation. 



Lloyd Williams (4) has recorded a feeble apoga- 

 mous development of the normal oospheres in Diclyota 

 dichotoma, (and subsequently (5) in Haiiseris), accom- 

 panied by pathological nuclear phenomena, and he states 



Diploid Plants<— 



(2«) 



Oospore (2;/) 

 t 



Haploid ,. 

 Tetraspores ^ ' 



Oosphere (;/) Sperm («) 

 t t 



-^Parent ^''■> 



Haploid Tetraspores* 

 in) 



fig. 2. Diagram illustrating life cycle if parent be regarded as 

 haploid. 



* This condition would ofier a partial analogy to the case of the abnor- 

 mal megaspores of Marsilia Drummondii, which are produced without 

 meiosis. In Marsilia, however, the spores are not haploid but diploid 

 (Bower, (l)). 



