OP THE OVTLES. 269 



converted into an ovary, and this again bearing Graafian 

 vesicles ! In Mr. Berkeley's carnation the change was 

 not so great, seeing that the nucleus of the ovule was 

 not developed, and sufficient evidence has been above 

 ^ven as to the foliar nature of the primine, while for a 

 leaf to be folded up so as to form a carpel is an ordi- 

 nary occurrence. 



It is worthy of remark that in these foUaceous 

 ovules there is never more than one coat, the secondine 

 and other integuments do not make their appearance 

 in these cases, and that very generally the change in 

 question accompanies a similar foliaceous condition in 

 the carpel, the margins of which are more or less dis- 

 united. 



Prof. A. Braun remarks that up to this date no such 

 change has been observed in the ovules of Monocoty- 

 ledons. 



Changes in the nucleus of the ovnle. The preceding re- 

 marks have had reference especially to the ovular coats, 

 but it is desirable also to allude to certain points 

 connected with the nucleus. Very frequently, when 

 the coat of the ovule is phylloid, as before described, 

 the nucleus is altogether wanting, though sometimes 

 it is present as a small cellular papilla ; very rarely is 

 it to be found in its perfect state. Occasionally the 

 nucleus is present in the guise of a small elongated 

 branch. Wigand cites ovular buds in every stage of 

 progress into a branch, sometimes even bearing indi- 

 cations of anthers. "Wydler has observed a similar 

 occurrence in ovules ofAUiana officinalis^ and Schimper 

 has described and figured specimens of NlgeUa dama- 

 scena in which the outer coats of the ovule were but 

 little changed, while the nucleus was replaced by a 

 leafy shoot. On one of the leaves of this latter was 

 found an imperfect ovule an ovule on an ovule ! 



Fig. 148 shows a floret of a species of Gaillardia, 

 in which the ovule was replaced by a leafy shoot which 

 had made its way through a chink in the ovary. In 



