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consolidated into a cup-like lid, called the operculum. " In Eudesmia, a 

 nearly-related genus, the calyx remains in its normal state, while the petals 

 are consolidated into an operculum. Punica is usually referred to this 

 order ; but the descriptions that have been published of it have been founded 

 upon so imperfect a view of its structure, that I may be permitted to dwell 

 upon it at some length, especially as 1 hope to shew thai it not only does 

 not differ from the order essentially, but that it docs not require to be dis- 

 tinguished from true Myrtacese even as a section. A consideration of the 

 real structure of this plant comes the more properly within the scope of 

 the present publication, because the genus has been considered the type 

 of a particular order (Granateoe) by Mr. Don, in which he is supported 

 by the high authority of Decandolle and Von Martius. The fruit. of the 

 Pomegranate is described by Goertner and Decandelle as being divided into 

 two unequal divisions by a horizontal diaphragm, the upper half of which 

 consists of from 5 to 9 cells, and the lower of 3 ; the cells of both being 

 separated by membranous dissepiments; the placenta; of the upper half pro- 

 ceeding from the back to the centre, and of the lower irregularly from their 

 bottom ; and by Mr. Don as a fleshy receptacle formed by the tube of the 

 calyx into a unilocular berry, filled with a spongy placenta, which is 

 hollowed out into a number of irregular cells. In fact, if a Pomegranate 

 is examined, it will be found to agree more or less perfectly with both 

 these descriptions. But it is clear that a fruit as thus described is at 

 variance with all the known laws upon which compound fruits are formed. 

 Nothing, however, is more common than that the primitive construction 

 of fruits is obscured by the additions, or suppressions, or alterations, which 

 its parts undergo during their progress to maturity. Hence it is always 

 desirable to obtain a clear idea of the structure of the ovarium of all 

 fruits which do not obviously agree with the ordinary laws of carpological 

 composition. Now, a section of the ovarium of the Pomegranate in various 

 directions, if made about the time of the expansion of the flowers before 

 impregnation takes place, shews that it is in fact composed of two rows 

 of carpella, of which three or four surround the axis, and are placed 

 in the bottom of the tube of the calyx, and a number, varying from, 

 five to ten, surround these, and adhere to the upper part of the tube of the 

 calyx. The placentae of these carpella contract an irregular kind of adhe- 

 sion with the back and front of their cells, and thus give the position ulti- 

 mately acquired by the seeds that anomalous appearance which it assumes 

 in the ripe fruit. If this view of the structure of the Pomegranate be cor- 

 rect, its peculiarity consists in this, that, in an order the carpella of which 

 occupy but a single row around the axis, it possesses carpella in two rows, 

 the one placed above the other, in consequence of the contraction of the 

 tube of the calyx, from which they arise. Now, there are many instances 

 of a similar anomaly among genera of the same order, and they exist even 

 among species of the same genus. Examples of the latter are, Nicotiana 

 multivalvis and Nolana paradoxa, and of the former Mulope among Mal- 

 vaceae ; polycarpous Rammculacea? as compared with Nigella, and poly- 

 carpous Uosacca as compared with Spiraa. In Prunus I have seen a mons- 

 trous flower producing a number of carpella around the central one, and 

 also, in consequence of the situation, upon the calyx above it; and, finally, 

 in the Revue Encychpcdiqxie (43. 762.), a permanent variety of the Apple 

 is described, which is exactly to Pomacea; what Punica is to Myrtacea;. 

 This plant has regularly 14 styles and 14 cells, arranged in two horizontal 

 parallel planes, namely, 5 in the middle, and 9 on the outside, smaller and 

 nearer the top; a circumstance which is evidently to be explained by the 

 presence of an outer scries of carpella, and not upon the extravagant hypo- 



