Mr. J. Miers on the Development 



is with the view of extending this inquiry that I have brought 

 together these remarks. 



It is evident from the foregoing exposition that the word 

 anatropal, as applied to an ovule developed under a certain con- 

 dition, is a very incorrect term, and one that might with pro- 

 priety be abolished, because it serves to perpetuate a prevailing 

 error ; but it may still be retained if we limit its signification to 

 a comparative instead of an active sense, — meaning, by the word 

 inverted, a different position of the radicle in regard to thehilum 

 in anatropal seeds — not as expressing any action of gradual in- 

 version of the nucleus and its tunics, as has been assumed. 



I will now proceed to show that the development of the raphe 

 is always normally ventral, or next the placenta, and that when 

 it assumes a dorsal position, this is due exclusively to a resupi- 

 nation of the entire ovule. I have already explained the differ- 

 ence in the incipient development of an anatropal and an atropal 

 ovule — that in the former the pullulation of the nucleus is never 

 from the extreme point, but always more or less removed from 

 it, and in general completely on one side of the plaeentary 

 sheath ; this is either on the upper or the lower face, but some- 

 times lateral, and in these cases the growth of the ovule is either 

 downwards or upwards, or laterally in regard to the axis of the 

 ovary, producing thus either pendent, ascending, or laterally 

 horizontal ovules. When the first appearance of the nucleus is 

 on the superior side of the funicular sheath, we have a pendulous 

 ovule, with the raphe necessarily on the ventral side of the pri- 

 mine (as shown in the marginal figures in p. 19), in all cases 

 where the point of its attachment upon the axis of 

 the carpel is at any sufficient distance above the 

 base of the cell to allow of its downward growth ; 

 but if this point of origin be contiguous to the 

 base, then the downward extension of the primine, 

 pressing against the bottom of the cell, causes the 

 ovule to incline upwards gradually into an erect 

 position (turning thus upon its funicle, as Mr. 

 Brown first sagaciously demonstrated in the case of 

 Euonymus), so that the ovule becomes completely 

 reversed, with the raphe upon its dorsal face. In 

 the same way, when the pullulation of the nucleus 

 is upon the lower side of the funicular sheath, 

 we have necessarily an ascending ovule with a 

 ventral raphe, produced by the upward expansion of 

 the sheath, as in the marginal figures, showing 

 the first and two later stages of this growth, which 

 prevails in all cases where the ovule has sufficient 

 room to expand itself; but where this production of the funi- 



Fies. 8-10. 



