Harris — Polygamy and Certain Floral Abnormalities. 199 



Norte; August; Parry. Corallitos, Chihuahua; Tlmrher. 

 Differs from the last in the excessively hispid stem and 

 branches, and in the much smaller flowers." In Gray's Sy- 

 noptical Flora the reference to Histoire des Solarium as the 

 place of first publication of this species is followed by the 

 parenthetical expression: '* Small-flowered form cult, at 

 Montpelier." 



I have seen none of the original material upon which 

 8. lieterodoxum Dun. is based, but have seen in the Engel- 

 mann Herbarium at the Missouri Botanical Garden, a good 

 series of S. citrullifolium A. Braun (some collected by Lind- 

 heimer and one sheet with Braun's name). In all of this 

 material the structure of the flower is very similar to 8. ros- 

 tratum Dun. The difference in the anther of the lower 

 stamen and the upper four is very pronounced and the stigma 

 is not at all capitate, while in the living material which I have 

 seen the differences in the size of large and small stamens is 

 even more pronounced than in 8. rostratum. The species is 

 interesting in this connection since there is a strong indication 

 of two forms of androecium in 8. lieterodoxum Dun., the one 

 in which the difference in the anthers is very pronounced and 

 the other in which there is very little difference. Of course 

 there is a possibility that 8. lieterodoxum Dun. represents 

 two distinct species, in which case 8. lieterodoxum will be 

 retained for the small-flowered form with nearly equal anthers 

 and capitate or subcapitate stigma, while 8. citrullifolium 

 A. Br. will be applied to the forms with the large strongly 

 zygomorphic flowers. 



The appearance of a dimorphism in the stamens of a 

 normally regular androecium has been noted in more than 

 one case, but this is the only instance which has so far come 

 to my notice in which a reduction to an almost regular form 

 of a pronounced Nycterium type like 8. lieterodoxum Dun. 

 might be suspected. 



The division of this vast genus of about 900 species is very 

 unsatisfactory. Wettstein m Die JSFaturlichen Pflanzenf ami- 

 lien has more than any other writer used the characters 

 offered by the stamens. The characters of his sections so 

 far as they concern us in this place are as follows : — 



