100 



the carpellae , the next thick walled 

 I ayer is the epidermis of the placenta. 

 The two epidermides are firmly grown 

 together. The two embryosacs have 

 grown so much that hardly any 

 tissue of the placenta remains. The 



two polar nuclei ly close together, 

 one antipodal cell is visible. 

 Fig. 38, 39 and 40, 41. PI. IX show 

 the presence of one oosphere, two 

 synergidae , two polar-nuclei close 

 together and one antipodal cell. 

 Double stain of Flemming. X 400. 



PLATE IX. 



Pig. 40, 41. See explanation of fig. 38 

 -41 PI. VIII. 



Fig. 42. Longitudinal section of embryo- 

 sac X 400. Haematoxylin-stain sho- 

 wing one synergide (S), the eggcell 

 (0), the endospermnucleus (E) and the 

 extremely large antipodal cell (A). 



Fig. 43, 44. Embryosac with eggcell, 

 two synergidae, endosperm nucleus 

 and binucleated antipodal cell (A) 

 X 250. Haematoxylin-stain. 



Fig. 45. Longitudinal section of part of 

 adult flower. X 175. Showing the 

 two polarnuclei in contact and the 

 thickwalled epidermal placentar tissue 

 X 250. 



Fig. 46. Embryosac with one ovum (0) one 

 synergide (S) a primary endosperm- 

 nucleus and three antipodal cells 

 A', A", A'", Haematoxylin-stain X 175. 



PLATE X. 



Fig. 47. Longitudinal section of a young 

 fruit. X 185. The styles have been 

 shed. A mechanical tissue has been 

 formed consisting of scleroid cells in 

 the form of a bell with the hantel 

 in the center. This last tissue is 

 formed from the inner epidermides 

 of the carpellae and the outer epi- 

 dermis of the top of the placenta. 

 The embryosacs have grown consi- 

 derably, an endosperm and embryo 

 has been formed in both sacs, while 

 in the sac to the left two synergidae. 



and one endospermnucleus in karyo- 



kinesis are visible. 

 Fig. 48. Crossection of male inflorescence 



showing arrangement of vascular 



bundles, somewhat leas than natural 



size. 

 Fig. 49. Abnormal embryosac with almost 



basigamic eggapparates and antipodal 



cell at the top. X 175. 

 Fig. 50. Isolated pollengrain , the exine 



shows clearly the spot where the 



grain was attached to its sistercells. 



X 1200. 



PLATE XI. 



Fig. 51. Longitudinal section of endosperm 

 of young grain with binucleated em- 

 bryo (0) and two synergidae (S, S'). 

 X 250. Double-stain of Fleniming. 



Fig. 52. Top of endosperm pictured in 

 fig. 51. X 600. 



Fig. 53. Longitudinal section of a ripe 

 seed. The section has not gone through 

 the median plain of the embryo, there- 

 fore it is not clear that the embryo 



has arisen from the eggcell. X 250. 



Fig. 54, Longitudinal median section of 

 embryo and some surrounding en- 

 dospermcells from a ripe seed, showing 

 clearly that the embryo develops 

 from the eggcell. 



Fig. 55. Karyokinetic nucleus of endos- 

 perm showing 8 chromosomes begining 

 to move towards the daughternuclei 

 to be formed. X 1200. 



