Pigott. — Notes on Nothopanax arboreum. 



611 



Endosperm. 



The early stages in the development of endosperm were seen, in which 

 the nuclei had become scattered through the vacuolate protoplasm. Later, 

 cell- walls were formed about them (fig. 14). By successive division of the 

 cells a dense endosperm is finally formed. This endosperm is continuous 

 through a number of consecutive sections both radial and tangential, the 

 only visible discontinuity being a very small break just below the micropyle 

 in one section (fig. 11). There was no appearance of any embryo in any of 

 these sections. It thus seems that here we have the formation of continuous 

 endosperm before any pollination was observed and before the appearance 

 of anv distinct embrvo. 



In several cases of endosperm viewed under the dissecting-microscope 

 there was the appearance of fibro- vascular strands traversing the endosperm. 

 This was also confirmed in several ovules sectioned. The fibro-vascular 

 strand is branched, and consists of annular xylem elements and phloem 

 elements with large elongated nuclei and square ends to the cells. The 

 fibro-vascular bundle of the funicle has annular vessels and phloem elements, 

 but no connection was established between the two (figs. 17 and 18). 



Embryo. 



At the earliest stage at which an embryo was observed it already con- 

 sisted of several cells — five to seven concentric rings of regular cells wholly 

 embedded in the endosperm (figs. 19 and 20). It was very small, and was 



Fig. 19. — Longitudinal section of ovule, showing embryo (e) 



immersed in endosperm, x 28. 

 Fig. 20. — Longitudinal section of embrvo. X 175. 



situated near the funicle, though whether at the micropylar or antipodal end 

 is uncertain owing to the complete disappearance of the micropyle. In 

 Umbelliferae generally, the hypocotyl points to the top of the ovule; in 



20* 



