

integument 



formed from the inner 



after fecundation the skins of the two ovules grow firmly 

 together by the sides which are in contact ; they gradually 

 become larger and harder, till at last they form in the ripe 

 fruit that loose bifid woody partition, to the faces of which, 

 hollowed out by the pressure of the nuclei, the seeds are 

 applied ; these seeds are winged at the apex, and are 

 covered by a single 

 membrane of the ovulum." 



So that Dr. Brown's opinion is, that the partition is 

 caused by the adhesion of two slit primines, one belonging 

 to each ovule; and that this is proved to be the fact by the 

 circumstance of the seeds having but one integument, 

 namely, the secondine, instead of two. But, ingenious as 

 this explanation undoubtedly is, we cannot help remarking, 

 that what Dr. Brown calls the primine, or outer integument 

 of the ovulum, may rather be considered of the nature of 

 an arillus ; and that the presence of but one integument 

 instead of two upon the ripe seeds, or even the ovulum 

 itself, is less demonstrative of the accuracy of his explana- 

 tion than it at first sight seems to be ; because there is 

 nothing to prove that Banksia has naturally more than one 

 seminal integument, or that it does not agree in the struc- 

 ture of its ovulum with Alnus and the like, which have 

 been proved by Mirbel never to have more than one in- 

 tegument to that part. 



J. L. 







