256 



On the Separation of the Pomegranate 



[Oct. 



tendentes, in inferiore processus irregulares ab ipso fundo" D. C. 

 (I.e.) 



*' The fruit of the pomegranate is described by Gsertner and DeCau- 

 dolle, as being divided into two unequal divisions by a horizontal dia- 

 phragm, 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 dissepi- 

 ments ; the placenta of the upper half proceeding 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, hov/ever, 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 ob- 

 tain 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 impregna- 

 tion 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 pla- 

 centae of these carpella contract an irregular kind of adhesion with the 

 back and front of their cells, and thus give the position ultimately ac- 

 quired by the seeds that anomalous appearance which it assumes in the 

 ripe fruit. If this viev^' of the structure of the pomegranate be correct, 

 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 tliey 

 exist even among species of the same genus. Examples of the latter 

 are, Nicotiana multivalvis and Nolan a paradoxa, and of the former Ma- 

 lope among Malvaceae ; polycarpous Ranunculacese as compared with 

 Nigella and polycarpous Rasacese as compared with Spiraea. In Prunus 

 I have seen a monstrous 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 Eucyclopedi que (43.762.) a perraa- 



