STEVENS: ENDOSPERM IN VACCINIUM CORYMBOSA 
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G. 1. Longitudinal section of embryo sac of Vaccinium corymbosum in two- 
celled stage; the fertilized egg and the remains of the pollen tube may be seen at the 
upper end and the remains of the antipodal cells at the lower end. 290. 
Fic. 2. Embryo sac of V. corymbosum which shows only free nuclear division. 
x 290. 
Fic. 3. Embryo sac from the same ovary as that in Fic. 2, showing two cross 
walls and evidence of free nuclear division. X 290. 
1G. 4. Longitudinal section of ovule of V. corymbosum showing few-celled en- 
dosperm with haustoria developing at either end. The inner cells of the integument 
are specialized to form a tapetum, being more densely crowded with protoplasm and 
generally smaller than the other cells of the 
integument. The walls of the epidermal 
cells are already somewhat thickened. 170. 

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