686 
Campbell. — Studies on the Araceae. 
ting. At the base of the lower one were two very large nuclei, and there were two 
free nuclei in the cavity of the sac. 
Figs. 1 6, 17. Nuclei from the lower sac shown in Fig. 15 more highly mag- 
nified. 
PLATE XXXI. 
Figs. 18, 22, 28 and 31 refer to Aglaonema commutatum , the others to a very 
similar, but possibly different, species grown at the Hope Gardens, Kingston, 
Jamaica, under the name Diejfenbachia Aglaonema. Figs. 19, 25, 28, 32, Leitz, 
oc. 3, obj. 3 ; 33, about 20 diameters ; the others Leitz, oc. 1, obj. 7. 
Fig. 18. Embryo-sac with ten nuclei, four at the chalazal end ( a ), the other six 
in a group at one side of the sac (two only shown in the section b). 
Fig. 1 9. Section of a fertilized sac, showing the forming endosperm at the base. 
Fig. 20. Young embryo, from near the chalazal end of the same embryo-sac. 
Fig. 21. Young endosperm of the same sac. 
Fig. 22. Group of four [antipodal (?)] cells from the same sac. 
Fig. 23. Embryo-sac with egg ( 0 ) and two synergidae ( c ), at the apex, and two 
nuclei, preparing to divide, at the antipodal end. 
Fig. 24. A similar embryo-sac, after fertilization. At the apex a young embryo, 
surrounded by large celled endosperm, apparently derived from the division of the 
basal nuclei shown in Fig. 23. 
Fig. 25. An older embryo-sac, with young embryo, em. 
Fig. 26. Two sections of an older embryo, sus , suspensor-cell. 
Fig. 27. Base of an older embryo-sac, with mass of tissue different from the 
endosperm, and possibly representing the embryo, as no other evidence of an 
embryo can be found. Above this mass was an elongated body ( p . t. ?), which 
may possibly have been the pollen-tube. 
Fig. 28. Section of embryo-sac, with older embryo, em. 
Fig. 29. Micropylar (root-)end of an older embryo. 
Fig. 30. Apex of the cotyledon of the same embryo. 
Fig. 31. Root- end of an embryo, showing slight differentiation of the tissues. 
Fig. 32. Embryo-sac, with mass of cells, perhaps an embryo, at the chalazal end. 
No embryo was present at the apex of the sac. 
Fig. 33. Section of older ovule, the embryo filling most of the embryo-sac end, 
the basal endosperm. 
Fig. 34. a, root-end ; b , central portion of the embryo shown in Fig. 33, st, the 
future stem-apex. 
PLATE XXXII. 
All figures refer to Spathicarpa sagittaefolia. Figs. 35, 53, Leitz, obj. 3, oc. 3 ; 
Fig. 56, about 8, Fig. 57 about 45 diameters ; Figs. 36, 37, 41-44, Leitz, oil imm. 
1/16, oc. 1 ; the others, Leitz, obj. 7, oc. 1. 
Fig. 35. Longitudinal section of mature pistillate flower of Spathicarpa sagittae- 
folia ; m, embryo-sac. 
Fig. 36. Young embryo-sac ; the second nuclear division is taking place ; the 
chalazal nucleus was also dividing. 
Fig. 37. a , egg-apparatus ; b , endosperm-nucleus from a mature embryo-sac. 
Fig. 38. Antipodal cells and endosperm-nucleus, from an embryo-sac of about 
the same age as Fig. 37. 
