1898] POLYEMBRYONY AND I7S MORPHOLOGY 223 
the larger comes not from the micropylar extremity of the 
embryo sac, but from some point on its wall a little removed. 
In other cases one sees a single embryo springing from the 
micropylar end and one or more from the walls, as in fig. 7. Or 
again, though rarely, there is a single embryo at the micropylar 
end,asin fig.g. There is a close resemblance between these 
figures and those given by Strasburger for Citrus Aurantium 
Vig. 37). If now these be examined in a still younger stage, it 
becomes clear that the embryos come from two different posi- 
tions: first, from a rather irregular mass of tissue which lies at 
~ micropylar end of the embryo sac, and extends thence along 
its wall; and second, directly from the wall itself. Both of 
these conditions are well shown in fig. zo. It is important to 
wotice, however, that some cases seeming to belong to the latter 
ey belong really to the former, as is illustrated by fig. 15, 
i Peet the wall-standing embryos are shown to spring really 
om the Mass at the micropylar end, but this is not the case 
mith all of the wall-standing embryos, for sections show that in 
ey Aes, i. é., fig. 10, these are entirely independent of that 
"oa ‘i 2 probable that the irregular embryos come as a rule 
Walls iv micropylar mass, while the regular ones are from the 
‘forall Ihave seen in that position have regularly two 
- Sotyledons. 
Se . far, in tracing backwards the origin of the polyembryony, 
2 ia is plain, and it is easy to find plenty of cases such as 
aa At this stage, the entire distinctness of the 
and its clo mass from the nucellus beneath (see figs. 70 and 11) 
trey thick maemblance to that described ee figured by a 
one to € traced to its origin ina fertilized egg cell, wen 
the wall-sta Suppose that we have here a similar case ; while in 
nding embryos, which are so sharply distinct from the 
Only % 2) that an origin from nucellus seems excluded, 
le, a ... hee eds endosperm cell would appear possi- 
Show that weg which is yet unknown." But the earlier stages 
, of these suppositions are incorrect. In a great 
'Thi 
IS Was ag 
™Y Own opinion in both cases at the time this paper was read before the 
