THE SPRUCE FIR 



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groups of cells, each consisting of a single very large 

 oval cell below and a well-defined column of small 

 cells above; each group is called an archegonium. 

 The large lower cell is the venter of the archegonium ; 

 the little column of cells above is the neck. 



FIG. 11 '2. Longitudinal section of an ovule of Picea at the 

 time of fertilisation, i, integument; nc, nucellus ; s, 

 part of the wing ; p, pollen -grains ; t, pollen-tubes ; c, 

 neck of an archegonium ; a, venter of archegonium con- 

 taining the ovum, o ; n, nucleus of ovum ; e t prothallus. 

 Magnified 9 times. (After Strasburger.) 



A general idea of tho structure of the whole ovule 

 at this period is given by Fig. 112. In this we sec 

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