THE MEZEREUM TRIBE. 151 



sarily unfounded, as will be ob^dous to you, if you call 

 to mind the rule I sometime since explained to you 

 ( page 131), that all the parts of a flower naturally 

 alternate with each other. Nevertheless, M. Dunal, 

 a French Botanist, has founded upon this and some 

 other cases, a theory of unlining in flowers (dcdouble- 

 ment)^ imagining that in all cases the corolla is pro- 

 duced by an unlining of the calyx ! 



But to return to our ]\Iezereum. Eight stamens 

 in two rows, one above the other, are placed on the 

 tube of the calyx ; and at the bottom of the cup is a 

 superior one-celled ovary (fig. 2.), with a nearly ses- 

 sile, tufted stigTiia (jig. S.). In the inside of the 

 ovary hangs a single ovule (fig. 3. c), with a foramen 

 (page 73, and ^(7. 3. Z>.), so conspicuous, that it may 

 be almost seen by the naked eye. When you first 

 pull the ovary of the Mezereum m pieces you will 

 probably imagine that the ovule is enveloped in a 

 loose hairy bag {fig. 3. o.) ; but upon scrutinizing it 

 more narrowly, you will find that the supposed bag- 

 is merely the lining of the ovary, which readily sepa- 

 rates from the shell and clings more or less to the 

 ovule ; so that you see the disposition to unline, which 

 is found in the calyx, is also conspicuous in the 

 ovarv. A section of the ovary, carefully made in a 

 vertical direction (fig. 3.), exhibits this very clearly, 

 presenting the appearance of two cavities, one above 

 the other, the upper one smooth and containing the 

 ovule, the lower one bristling ^Aith crystalline points, 

 and empty. 



The ripe fruit of ?>Iezereuni is ivd and succulent 



