ON NAIAS GRAMINEA DEL., VAR. DELILEI MAGNUS. 



15 



sexes in the same fascicle, at equal stages of development (figs. 67 

 and 68), and mature and immature flowers enclosed by the same 

 bract (see figs. 81 and 86). 



The flowers begin to occur 

 immediately within the axil of 

 the first pair of leaves in each 

 fascicle, but there is frequently 

 an outlying pair of leaves below 

 the fascicle which does not con- 

 tain flowers. The oldest flowers 

 are always at the base of the 

 fascicle. When mature, the fruits 

 are plainly visible to the naked 

 eye (see Delile's figure on Plate 

 250, fig. 4), but they can be 

 detected, when present, by the 

 touch. The female flowers are 

 rarely solitary, but occur in twos, 

 threes, or fours ; in the earlier 

 stages of development they are 

 sometimes more numerous. The 

 male flowers are more often soli- 

 tary. In the centre of the fascicle 

 are the youngest flowers (see figs. 

 68 and 69). 



In appearance the flowers look 

 as if they were ordinary anthers 

 and pistils, i. e. t that they possess 

 no perianth ; but Dr. Magnus 

 has shown that their outermost 

 covering is really a perianth 

 which more or less closely invests 

 the anthers and pistils. In fig. 

 16 ' on Plate 251 the perianth 

 has been drawn back from the 

 exposed anther of N. major. Figs. 

 22, 24, 25, and 28 show the 

 natural reflexion of the perianth- 

 leaves in the male flower of N. 

 major. 



All the flowers are sessile, 

 and I have endeavoured to con- 

 vey, in the accompanying figures, 

 accurate representations of each. 



X. — The Pistillifekous Flower, 



Fia. 69. 



The female flower consists of 

 an elongate flask-shaped body, 

 with a long neck which bifurcates at its free end (figs. 68 and 70), 

 like the bifid stigma of a Car ex, such as C. ovalis. The outer 

 covering is the perianth ; the body which it encloses is the pistil. 



