210 Mr. Griffith on the Ovulum of Santalum, 



Fig. 8. Placenta, with two fertilized ovula, one a good deal less advanced than the other. 

 The course of the posterior extensions is traced out. 



Fig. 9. Whole of the embryonary sac above the bulb. The cellularity of the vesicle is com- 

 mencing by the usual nucleary aggregation, and its lower part appears as if cut off 

 from the upper. This is, I think, the usual appearance. The pollen tube is still 

 seen in adhesion. 



Fig. 10. Apex of an ovulum, or young seed, more advanced, a. Vesicle, b. Lax embryonic 

 tissue, c. Condensed apex of ditto. 



Fig. 11. Embryo of the same detached. The upper portion of the vesicle is undivided ; this 

 is almost always the case. The letters have the same references as in fig. IG. 



Fig. 12. Longitudinal section of young fruit. 



Fig. 13. The entire embryonary sac, of this period, dissected from its surrounding tissues, 

 with the exception of the apex of the nucleus. 



Tab. XVIII. 



Osyris Nepalerms. 



Fig. 1. A longitudinal section of the flower, before expansion, a. The part which may be 

 supposed to be derived from the adhering integuments of the flower, b. The part 

 which I suppose to correspond to the ovarium, c. The placenta, d, d. Two ovula. 

 e. The stigmata. 



Fig. 2. The placenta of the same, detached. The ovulum to the right is somewhat dis- 

 placed. 



Fig. 3. Ovulum, during the expansion of the flower, a. Nucleus, b. Protruded mammiUa 

 of embryonary sac. c, c. Included portion of ditto. It does not appear to be pro- 

 longed downwards. 



Fig. 4. Placenta, after impregnation, but before any considerable sphacelation of stigmata. 

 One of the pollen tubes is accidentally ruptured ; the other is seen in contact with 

 the protruded apex of the embryonary sac. The dotted line a, a, a, a, is intended 

 to show the course of the embryonary sac for some distance beyond the base of 

 the placenta. 



Fig. 5. Upper half of one of the ovula, intended to show the relation between the pollen 

 tube and the apex of the embryonary sac. a, a. Apex of nucleus, b. Protruded 

 end of embryonary sac. 



Fig. 6. Placenta, about the period of the fall of the perianthium, detached. 



Fig. 7- Ovulum from the same. a. Nucleus, b. Cellular growth on the protruded apex of 

 the sac ; to it a short filament is seen adhering, and in it are seen angular grumous 

 bodies of considerable size. c. Part of the embryonary sac. 



