Osyris, Loranthus anrf Viscum. 211 



Fig. 8. A similar ovulum. The dotted line indicates the course of the embryonary sac. 



Fig. 9. The apex of an embryonary sac and the cellular growth, from an ovulum of the same 

 period, under pressure. It now appears as if the cells were confined to the mar- 

 gins of the tube. The embryonary sac is separable from the cells even at this 

 stage. The cells are crowded with molecular matter, as is the case in all new cel- 

 lular growths with which I am familiar. 



Fig. 10. Portion of the placenta of a young fruit, with ovulum and young seed. The dotted 

 line represents the course of the embryonary sac. 



Fig. 11. Embryo. 



Fig. 12. Longitudinal section of a fruit considerably advanced, a. Tegumentary tissue. 

 b. Circumference of ovarium, now commencing to be indurated, c. Loose inner 

 tissue, most dislocated round the seed and placenta, d. Communicating canal, 

 still visible, e. Placenta and its stalk, f. Cellular mass, in which albumen is 

 now deposited, g. Embryo. 



Tab. XIX. 



Loranthus globosus. 



Fig. 1. Longitudinal section of an ovarium, 1| line long. The central tissue of the ovarium, 

 which is (or ought to be) more transparent than the rest, is seen to be occupied 

 by three sacs, the course of which is pointed out (especially in the upper frds) by 

 a profusion of granules. The sacs at this period are scarcely separable, nor is 

 their membrane at all distinct : along their lines iodine causes a strong tinge of 

 violet. The sacs extend up into the epigynous disc ; some at this period even reach- 

 ing pretty closely to the base of the style. The dense coniform base of the central 

 tissue, which subsequently eifects such changes in the situation of the embryo, 

 now exists. 



Fig. 2. Upper end of an embryonary sac, soon after the fall of the perianthium. Owing to 

 the presence of grumous bodies in the apices of the sacs, I never traced the abso- 

 lute continuity of the inclosed filaments with those projecting from their apices. 



Fig. 3. Lower half of an embryonary sac at rather a later period. The limits of the sac are 

 always difficult to ascertain, as there appears to be a tissue formed from their 

 ends. In this instance the limit of the sac is perhaps at a, and that of the tissue 

 subsequently formed at b. The more condensed tissues of the embryo have made 

 their appearance at c. 



Fig. 4. From a later period. Three sacs are seen, dissected out of the ovarium : that on 

 the right hand has not been fertilized, and remains unchanged; within the others, 

 one of which is broken, albumen is seen to be developed at a, a ; and the albumina 

 VOL. XIX. 2 F 



