Chap. IV. LYTHEUM GE^FFEEI. 165 



Finally, it has now been shown that Lythrum salicaria 

 presents the extraordinary case of the same species 

 bearing three females, different in structure and func- 

 tion, and three or even five sets (if minor differences 

 are considered) of males ; each set consisting of half- 

 a-dozen, which likewise differ from one another in 

 structure and function. 



Lythrum Orcefferi.—l have examined numerous dried flowers 

 of this species, each from a separate plant, sent me from Kew. 

 Like £. salicaria, it is trimorphic, and the three forms appa-r 

 rently occur in about equal numbers. In the long-styled form 

 the pistil projects about one third of the length of the calyx 

 beyond its mouth, and is therefore relatively much shorter than 

 in L. salicaria ; the globose and hirsute stigma is larger than, 

 that of the other two forms ; the six mid-length stamens, which 

 are graduated in length, have their anthers standing close above 

 and close beneath the mouth of the calyx; the six shortest 

 stamens rise rather above the middle of the calyx. In the mid- 

 styled form the stigma projects just above the mouth of the 

 calyx, and stands almost on a level with the mid-length stamens 

 of the long and short-styled forms ; its own longest stamens 

 project well above the mouth of the calyx, and stand a little 

 above the level of the stigma of the long-styled form. In short, 

 without entering on further details, there is a close general 

 correspondence in structure between this species and L. salicaria, 

 but with some differences in the proportional lengths of the 

 parts. The fact of each of the three pistils having two sets of 

 stamens of corresponding lengths, borne by the two other forms, 

 comes out conspicuously. In the mid-styled form the pollen- 

 grains from the longest stamens are nearly double the diameter 

 of those from the shortest stamens ; so that there is a greater 

 difference in this respect than in L. salicaria. In the long- 

 styled form, also, the difference in diameter between the pollen- 

 grains of the mid-length and shortest stamens is greater than 

 in L. salicaria. These comparisons, however, must be received 

 with caution, as they were made on specimens soaked in water, 

 after having been long kept dry. 

 Lythrum thymifolia. — This form, according to Vaucher,* is 



'Hist. Phys. des Plantes d'Europe,' torn ii, (1841), pp. 369, 371. 



