18 



Dansk Botanisk Arkiv, Bd. 2. Nr. 6. 



Fig. 8. Cymodocea isoetifolia. 



a, Male flower; b, Female flower. 



(4/j nat. size.) 



ary axis usually has one or two leafy bracts inserted above those 



leafy bracts from the axils of which the secondary axes arise; 



this arrangement occurs again in the youngest one-sided parts 



of the inflorescence, whereas in 

 its median part each axis has 

 only the two leafy bracts sub- 

 tending branches. 



The flowers are covered by 

 the inflated sheaths of the leafy 

 bracts. In the female flower 

 the four stigmatic branches are 

 seen above the sheaths. In the 

 male flower the anther must be 

 supposed to appear when it is 

 ripe, but I have not succeeded 

 in finding this stage. All the 

 male flowers examined by me had 



a sessile double stamen inclosed in the sheath or sheaths (Fig. 8 a); 



the filament is so short that the anther is almost sessile, but 



most probably it elongates suddenly 



thus enabling the anther to extend 



beyond the sheath, or perhaps the whole 



anther breaks off when ripe. 



The structure of the male flower 



is the same as in other species of Cy- 

 modocea, and there seems to be no dif- 

 ference between the two species. In 



both the flower consists only of two 



connate stamens. The anthers are ex- 



trorse and the whole flower looks like 



one 8-locular stamen. A transverse sec- 

 tion through the middle shows four 



bilocular parts, and it is only in the 



upper half that the two anthers become 



distinct from each other (Fig. 9). In 



C. isoetifolia the anther is 3.5 — 4.2 mm 



long and 1.7 — 2.0 mm thick, and the 



pollen sacs are often somewhat twisted 



(see Fig. 4 6). In the two male flowers Fig- 9< Cym , isoetifolia. 



of C. manatorum which I have been able Transverse sections of the 



to examine, the anthers were a little S^MhrouA^d! 



shorter and broader: 3.1 and 3.6 mm die. (About 20 /i nat. size.) 



