342 Kirkwood : Pollen-tube in Cucurbitaceae 



Description of plates 16 and 17 



Plate 16 



1. Diagrammatic figure representing longitudinal section through gynoecium of 

 Melothria. Course of pollen-tube (P. /.) intercellular. 



2. a, 6, c. Pollen-tube showing plugs. 



3. Longitudinal section through gynoecium of Micrampelis. Conducting-tissue 



shaded. 



4. Ovary of same at right angles to figure 3. 



5. Longitudinal section through ovary of Cyclantkera, showing path of pollen- 



6. Diagram of micropylar region of ovule of Cyclanthera, showing dilation of 



tubes. 



pollen-tube, P. t. 



7. Ditto, Melothria. 



8. Ditto, Micrampelis. 



Plate 17 



9. Conducting-tissue of Melothria on placental folds. Pollen-tube in transverse 

 section. X 44°- 



10. Conducting-tissue on funicle of ovule of Melo Aria. X 44°* 



1 1. Conducting-tissue of Micrampelis. Transverse section of pollen-tube. X 44°- 



12. 13. Transverse section through neck of nucellus, in Cyclanthera, before and 

 after passage of pollen- tube, P. t. X 44°- 



14. Conducting-tissue in ovary of Cyclanthera. PL, placenta ; 0. w., ovary-wall ; 

 P. t., part of pollen-tube. X 44°» 



15. Same showing pollen-tube (P. t.) passing under some cells of conducting- 

 tissue. X 44°« 



