8 4 



THE WATERLILIES. 



The structure of the filament resembles that of the inner petals. 

 The epidermis bears hair-bases, the parenchyma is made of soft, rounded 

 cells, and air-spaces are present. There are one to three or more 

 longitudinal vascular bundles. The mature anther is covered by a single 

 layer of square cells, a little deeper than wide, with thickened inner and 

 lateral walls ; the outer wall is unthickened. The anther cells are 

 parallel and introrse, with longitudinal dehiscence (Fig. 37, a, b}. In Lotos 

 and Brachyceras the division between the two loculi of each cell is 



quite evident after dehiscence, 

 as the pollen dust remaining 

 after most has been shed lies 

 in two pairs of grooves on 

 the inner face of the anther. 

 Chifflot (1902) has recently 

 made a minute study of sporo- 

 phyll structure in Nymphaea- 

 ceae, including nine species of 

 Nymphaea. He finds slight 

 differences in the venation of 

 the stamens. He sums up his 

 work (which I have not had 

 time to verify) in a classifica- 

 tion based on the distribution of idioblasts (" sclerites ") and stomata in 

 the stamen, and of idioblasts in the carpels (1. c., p. 280). We quote this 

 in translation. The names are correct and mostly well chosen, unless 

 in the case of "A r . blanda." The material of this came from the Kew 

 Herbarium, where N. rudgeana occurs under the name of TV. blanda, and 

 is much more plentiful. 



SYNCARPIAE : 



Idioblasts rare in the filament, always present in the anther a. 



Idioblasts absent from filament, anther, and ovary (Xanthantha) A', flai'a . 



Idioblasts present in the filament and outer part of ovary (Castalia) c . 



a. Stomata present on upper epidermis of filament (Lotos). Idioblasts absent from 



mesophyll of ovary, present in carpellary styles A', thermalis . 



a. Stomata wholly absent from the stamen (Hydrocallis) b. 



b. Idioblasts of but one kind, present in filament and anther " N. blanda." 



b. Idioblasts of two kinds, localized in the anther .V. oxypetala. 



c. Idioblasts absent from the anther, but numerous in the carpellary rays d. 



c. Idioblasts present in anther, rare in carpellary ray N, tuberosa. 



d. Stomata absent from whole stamen N. alba. 



d. Stomata present at base of loculi on both faces of filament. X.pygmaea [ = A T . tetragona}. 



FIG. 3!. a. h, transverse sections of anther of N. tiara near 

 base and near apex, respectively ; c, vertical section of stigma, 

 showing papillae, N. tubernsa. All after Chifflot. 



