168 HETEROSTYLED TRIMORPHIC PLANTS. CHAP. IV. 



above-described anther of the Lagerstroemia ; we may there- 

 fore suspect that this species was once heterostyled, and 

 that it still retains traces of its former state, together with 

 a tendency to revert more completely to it. It deserves 

 notice, as bearing on the nature of Lagerstroemia, that in 

 Lythrum hyssopifolia, which is a homostyled species, some 

 of the shorter stamens vary in being either present or 

 absent, and that these stamens are altogether absent in 

 L. thymifolia. In another genus of the Lythracese, namely 

 Cuphea, three species raised by me from seed certainly 

 were homostyled; nevertheless their stamens consisted of 

 two sets differing in length and in the colour and thickness 

 of their filaments, but not in the size or colour of their pol- 

 len-grains ; so that they thus far resembled the stamens of 

 Lagerstrcemia. I found that Cuphea purpurea was highly 

 fertile with its own pollen when artificially aided, but 

 sterile when insects were excluded.* 



OXALIS (GEBANIACE.E). 



In 1863 Mr. Eoland Trimen wrote to me from the 

 Cape of Good Hope that he had there found species of 

 Oxalis which presented three forms; and of these he 

 enclosed drawings and dried specimens. Of one species 

 he collected 43 flowers from distinct plants, and they 

 consisted of 10 long-styled, 12 mid-styled, and 21 

 short-styled. Of another species he collected 13 flowers, 

 consisting of 3 long-styled, 7 mid-styled, and 3 short- 



* Mr. Spence informs me that some specimens of Mollia lepidota 



in several species of the genus and speciosa from Kew, but could 



Mollia (Tiliacese) which he col- not make out that their pistils 



lected in South America, the differed in length in different 



stamens of the five outer cohorts plants ; and in all those which 



have purplish filaments and green I examined the stigma stood 



pollen, whilst the stamens of the close beneath the uppermost 



five inner cohorts have yellow anthers. The numerous stamens 



pollen. He therefore suspected are graduated in length, and the 



that these species might prove to pollen-grains from the longest and 



be heterostyled and trimorphic : shortest ones did not present any 



but he did not notice the length of marked difference in diameter, 



the pistils. In the allied Luhea Therefore these species do not ap- 



the outer purplish stamens are pear to be heterostyled. 

 destitute of anthers. I procured 



