Campbell. — Studies on the Araceae. 687 
Fig. 39. Antipodal cells and polar nuclei from a younger sac. 
Fig. 40. Embryo-sac after fertilization. The sexual nuclei are fusing in the egg- 
cell, and the endosperm formation has begun. 
Fig. 41. Fertilized egg of Fig. 40, more enlarged, showing conjugation of the 
sexual nuclei. 
Fig. 42. Chalazal end of the same sac, more highly magnified, showing the 
enlarged antipodal cells and young endosperm. 
Fig. 43. Chalazal end of an older embryo-sac. 
Fig. 44. Egg-cell, with fusion of the sexual nuclei almost completed. One of 
the synergidae is clearly evident. 
Figs. 45-47. Young embryos, sus , suspensor. 
Fig. 48. Young embryo surrounded by endosperm. 
Figs. 49-52. Median longitudinal sections of older embryos, showing the 
variation in form, and in the development of the suspensor. 
Fig- 53* Three longitudinal sections of an older embryo ; a , a nearly median 
section ; st , stem-apex ; r , root ; cot , cotyledon. 
Fig. 54. Nearly median section of the root portion of the same embryo as 
Fig. 53, more highly magnified. 
Fig. 55. Central region of the same embryo showing the stem-apex, st. 
Fig. 56. Longitudinal section of a nearly full-grown seed, showing the small 
embryo, eni , and the large antipodals, ant ; enlarged about eight times. 
Fig. 57. The lower part of Fig. 56, more enlarged. 
Fig. 58. Endosperm cells from a nearly ripe seed. 
Fig. 59. Nucleus from one of the antipodal cells. 
