CONIFERM. 



523 



gonia of Taxus are short ; in those of the Abietinese the oosphere is elongated ; 

 in the Cupressineae it becomes angular from the pressure of the adjacent cells. 

 The number of the archegonia which are formed in the endosperm beneath the 

 apex of the embryo-sac is very various ; Hofmeister and Strasburger stale that in 

 the Abietineae it is from three to five, in the Cupressineae from five to fifteen 

 (according to Schacht it may even be thirty), in Taxus baccata from five to eight. 

 The continuous growth of the surrounding endosperm causes the formation of 

 funnel-shaped depressions above the archegonia, which in some Abietineae are but 



F'<^- 2SS-—y>"i'perus communis (after HofmeisteH- / three archegonia cp close beside one another, in two of them 

 the rudimentary embryo ei\s seen at the lower end of tlie oosphere, rf neck-cells, / pollen-tube (July z8) (X 300). // a 

 similar section, ^^ the endosperm, v v the embryos : /// lower end of one of a suspensor with the rudiment of the embryo 

 eb; /K longitudinal section of the nucellus kk, e the endosperm, e' portion of the endosperm that is bn>keu up,/ pollen- 

 tube, cp the archegonia, v the suspensors (beginning of August) (X 80). 



shallow, in Pinus Pmaskr, P. Sirobus, &c., deep and narrow. In these species each 

 of the funnel-shaped depressions leads down only to the neck of one archegonium ; 

 in the Cupressineae {Calliiris, Thuja, and Juniperus), where they lie closely crowded 

 together, the cluster of them is walled round by the endosperm, and a funnel is 

 formed common to them all, which still remains closed by the cell-wall of the 

 embryo-sac. 



Fertilisation. The pollination of the ovules takes place before the archegonia 

 are formed in the .endosperm ; the pollen-grains, having reached the apex of the 



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