348 Campbell. — Studies on the Araceae , III. 
Fig. 23. Upper part of an older embryo-sac; the embryo is four-celled; nu., the cap of cells 
formed from the apex of the nucellus. 
Figs. 24-26. Longitudinal sections of somewhat older embryos. Leitz, im. 1/16, oc. 1. 
Fig. 27. Upper part of embryo-sac and older embryo, x about 250. 
Fig. 28. Median transverse section of embryo. Leitz, im. 1/16, oc. T. 
Fig. 29. Two longitudinal sections of an older embryo, x about 100. st. } stem-apex; cot., 
cotyledon ; rc., root-cap. 
Fig. 30. Nearly median section through the base of the same embryo, x about 250. 
Fig. 31. Median section of an older embryo. 
Figs. 32, 33. Longitudinal sections of nearly full-grown embryos, x about 45. 
Fig. 34. Stem-apex and second leaf of the embryo shown in Fig. 32. x about 25c. 
Fig. 35. Median section through the root-apex of the full-grown embryo, x 250. pl. } plerome- 
cylinder of the root. 
Fig. 36. Transverse section of full-grown embryo. 
Fig- 3 7. Cells from the embryo, containing raphides, r. 
PLATE XVI. 
All figures refer to Nephthytis LibeHca. 
Fig. 38. Longitudinal section of young ovule, x about ico. 
Fig. 39. Nucellus of the same ovule, more highly magnified, showing two archesporial cells. 
Fig. 40. Nucellus from an ovule of about the same age; several archesporial cells are present, 
but the exact number is doubtful. 
Fig. 41. Two sections from a probably abnormal ovule, with a large number of archesporial cells. 
Fig. 42. Two sections from an ovule showing unusual development of the sporogenous tissue. 
Nuclear divisions have taken place within the cells, and it is not possible to say how many primary 
archesporial cells are represented. There were twenty nuclei in all. 
Fig. 43. Three sections of an older ovule ; there is apparently a single embryo-sac divided by 
partitions into three chambers ; a second smaller embryo-sac with two nuclei is also present, sp 2 . 
Fig. 44. Embryo-sac with a single very large apical nucleus, and three antipodals (?) at 
the base. 
Fig. 45. Embryo-sac with two nuclei separated by a membrane. About the nuclei were 
numerous starch granules ; a second embryo-sac with a single nucleus was present. 
Fig. 46. Four sections of a large embryo-sac approximating the ordinary angiospermous type; 
a, shows two synergids (?), and b, the egg-cell ; two antipodal cells were present, and three free 
nuclei (polar nuclei?), one of which, c, was in an advanced prophase of division. 
Fig. 47. Embryo-sac with large fusion-nucleus in the upper part. 
Fig. 48. Section of ovule with embryo-sac containing but two nuclei. 
Fig. 49. Upper part of sac shown in Fig. 48 ; the nucleus is preparing for division. 
Fig. 50. Lower nucleus from the same sac in process of division ; about fifty-six chromosomes 
could be counted. 
Fig. 51. Two sections of an embryo-sac containing a two-celled embryo, em. The sac was 
divided into two cells; no traces of antipodal cells could be found, x about 100. 
PLATE XVII. 
All figures refer to Nephthytis Liberica . 
Fig. 52 .a, upper part, b , base of an embryo-sac with a normal egg-apparatus, but only a single 
nucleus at the base. 
Fig. 53- Embryo-sac with a single cell (egg ?) at the apex, and a large mass of cells, about 
fifteen in number, at the antipodal end. Two free nuclei, e.n. } one in process of division, were also 
present. 
Fig. 54. Section of ovule and embryo-sac, the details are shown in Fig. 55. 
Fig. 55. a-d, four sections of the apex, e, antipodal region of the sac shown in 54 ; there were 
five nuclei in the antipodal region. 
Fig. 56. Two fusing nuclei from a sac of about the same age as that shown in 55. 
