314 THE JOURNAL OF BOTANY 



allows. The older spatbes are easily opened ; the two valves are 

 distinct to the base and protect the rather stout central axis, which 

 is densely covered with a grape-like mass of stamens, each with a 

 short filament and a horizontally somew'hat elongated anther. 

 The arrangement of the stamens is presumably racemose, but 

 development is apparently rapid, and in the most advanced spatbes, 

 which are very easily detached, the condition of the anthers is very 

 uniform. Under high magnification the anthers are seen to be 

 two-celled and to contain pollen-mother-cells which are dividing 

 crosswise into four (fig. 12). No later stage was found, and it may 

 be assumed that the spathe with its short stalk is released and 

 floats to the surface of the water. The broad concave spathe- 

 valves may then spread and form floats for the central stamini- 

 ferous axis, facilitating its passage to the emerging female flow^er, 

 and recalling the method of pollination in VaUisneria. 



The arrangement of the female spatbes is somewhat similar. 

 In the axils of generally three leaves, which are almost at the 

 same level, are developed sessile leaf- and flower-bearing shoots, 

 which together form an apparent whorl at intervals along the 

 length of the stem and become closely crow^ded towards its apex. 

 The leaf subtending the reduced whorl has a broader base ; the 

 axillary shoot bears at its base several long narrow foliage-leaves, 

 immediately above which the axis bears in succession a number 

 of broadish sheaths, each of which envelops a foliage-leaf and a 

 flower. This arrangement is best seen in the young shoots at the 

 apex of the stem, in each of wdiich an indefinite succession of 

 flowers is indicated. It suggests, as in the male plant, an inde- 

 finitely prolonged flow^ering period. Around the base of each flower 

 are several hair-like structures similar to those found associated 

 with the male flowers. When mature the spathe is carried to the 

 surface of the water by the lengthening of the peduncle, which is 

 many times its length, and the flower expands at the surface. 

 The three broad red-purple spreading petals alternate with three 

 deeply bifid spreading stigmas ; there is no trace of a second 

 whorl of perianth-leaves or of staminodes. In section the ovary 

 is slightly three-sided, a character which becomes exaggerated 

 after pollination, and is due to the development of three low 

 longitudinal ridges (fig. 6). The ovary walls are covered internally 

 with upw^ardly directojd short-stalked ovules, each of w^iich has 

 a single integument. The developing fruit bears the withering 

 perianth at the apex and is invested below by the remains of the 

 spathe ; in this condition it is withdrawn below the surface of 

 the water by spiral contraction of the peduncle. Eipe fruit was 

 not found. A slight difference in the width of the three sides 

 of the fruit, one being larger than the other two, associated with 

 a slight inequality of the perianth-segments w4iich was observed 

 in one or more of the flowers examined, indicates a tendency to 

 zygomorphy. 



The affinity of this interesting little plant is obviously with 

 VaUisneria, though the habit strongly recalls the African genus 

 Lagarosiphon. VaUisneria caulescens Bailey & F. v. MuelL, from 



