1914] MARTIN— LEGU MINOS AE 16; 



multicellular archesporium usually occurs, and so far as observed 

 a longitudinal row of 4 megaspores is always formed. 



Guignard gives no account of a multicellular archesporium 

 in any of the species which he studied, but the early stages of the 

 ovules were examined without sectioning, and it is probable that 

 present methods would give different results. He found parietal 

 tissue in all species studied, but the greatest amount in the Mimo- 

 soideae and Caesalpinioideae. 



The following records show that a multicellular archesporium 

 occurs in other families of the Rosales. Miss Pace (6) found a 

 multicellular archesporium in Parnassia and Saxijraga. Webb 

 (14) reported the same type in Astilbe. Shoemaker (9) found 

 several archesporial cells in Hamamelis; and Coulter and Cham- 

 berlain (2, pp. 58, 59) in a summary of the literature show that 

 a multicellular archesporium prevails among the Rosaceae. 



The filiform apparatus in Trifolium pratense differs from that 

 described by Pace in Parnassia and Saxijraga and by Strasburger 

 in Polygonum (11) and Santalum (12), in that no notch appears. 



Guignard (3, p. 142) states that the polar nuclei fuse before 

 fertilization except in the subfamily Vicieae, and that the fusion 

 nucleus rests on the median line of the sac in the Mimosoideae and 

 Caesalpinioideae, and against the inner side of the sac in the Papilio- 

 noideae. In the five species treated in this paper, the fusion of the 

 polar nuclei was found to await fertilization, and their position 

 is median in Medicago saliva, but may be either median or parietal 

 in the species of Trifolium, and always parietal in Vicia americana. 



Guignard (3, p. 141) found the antipodal cells persisting till 

 fertilization in the Mimosoideae and Caesalpinioideae, but dis- 

 appearing earlier in the Papilionoideae. Saxton (7) found the 



antipodals persistent and functioning as haustoria in Cassia tornen- 

 tosa. 



Summary 



Features common to the five species are as follows: (1) campy- 

 lotropous ovules; (2) two integument-, the outer preceding the 

 inner; (3) a multicellular archesporium; (4) one parietal cell cut 

 off which gives rise to more or less parietal tissue; (5) the pro- 

 duction of a row of 4 megaspores; (6) the rapid d truction of 



