74 
so 
ASCLEPIADEM. 
the viscous matter dissected by the furrows, see fig. 2. 
It slips likewise into the furrows along, which it seems 
to produce the sphacelated appearance: thus it likewise 
produces on the surfaces over which it is applied. 
The tubes reach the ovula and become applied to the 
foramina in a firm manner. In the instance figured, 
three tubes have united into one, these together with the 
common one, particularly the latter close to its entrance, 
contain granules and what appear to be coagula. No 
change is visible in the ovule except a slight opacity 
towards the foramen. This opacity is not central. the 
granules do not appear to be mobile while in the tubes, 
when they have escaped into the water surrounding 
the object, they are very mobile. The motion con- 
sists chiefly of rotation on their axis, there is scarcely 
any locomotion. In the above, 3 tubes are not united 
into one as it appears from the drawing; the appear- 
ance is owing to another tube being doubled on itself 
beneath that proceeding to the ovula. The tubes do 
not appear to enter far, if at all into the ovulum. 
10. Group of Pollen grains which have dehisced. 
The conclusions that I deduce from the above imperfect 
oss) 
9 
e 
4. That the tubes do reach the ovula, and become RT : 
observations are as follows : 
. That impregnation takes place (generally) by the emis- 
sion of tubes which enter the base of the stigma, 
proceed down the style, and are ramified over the pla- _ 
centa. 
That the emission takes place extra antheram, and ator — 
about the grooves on which spaces alternate with the 
anthers and communicate directly with the base of the 
stigma. 
. That to aid this emission, these spaces are always filled j 
with viscid mucus at the time of impregnation. 
plied to the foramina, which are situated close to the hi — 
ree MES 
