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are smaller than the two others. Upon opening this pistillum we find thaf 

 there are two parietal placentse corresponding with the smaller stigmata, and 

 that there are no placentee opposite the larger stigmata; in other words, 

 that it is formed of four simple pistilla, two of which are opposite and ovuli- 

 ferous, with their placentae in the usual place, alternating with themselves; 

 and two nearly abortive, destitute of placentse, consequently not ovuliferous, 

 and so nearly suppressed by the superior energy of their two neighbours, 

 that their existence would have been unknown but for the stigmata which 

 indicate their presence. This is one way of understanding Eschscholtzia ; but 

 as the ovula are not inserted in the placentse in a double row, but rather 

 confusedly arranged in several rows, it may also be assumed that the 

 lateral, imperfect, half-obliterated stigmata have a line of placenta, with 

 ovula appertaining to themselves, but so confounded with the placentae of 

 their lateral and more powerful neighbours, that, in consequence of their 

 close approximation, they cannot be distinguished. We, however, incline 

 to the farmer of these two opinions. Let this be as it may, upon either 

 supposition, the structure of Cruciferous pistilla is, we think, susceptible of 

 explanation. We shall, for convenience, reason upon the former of the two 

 hypotheses. 



If we compare the fruit of Eschscholtzia and Cruciferae, we shall at first, 

 perhaps, be led to believe that while they have a certain degree of resemblance 

 in some points, they nevertheless differ widely in others of more importance ; 

 we find both of them with two opposite parietal placentae, connected with a 

 quaternary arrangement of the other parts of the flower, and that in both 

 instances their placentae are opposite to stigmata. But we also see that in 

 Cruciferae dehiscence takes place by the separation of two valves from the 

 sides of the siliqua, leaving the placentae undivided ; while in Eschscholtzia it 

 takes place through each placenta, half of which, therefore, adheres to each 

 edge of the two valves into which the fruit finally separates. But if we 

 look into their structure a little more narrowly, we shall perhaps find that 

 these differences are not only capable of reconciliation, but that they explain 

 each other. 



L 



F- 



The fruit of Cruciferae is separable into four parts — that is to say, 

 into two valves without stigmata, and two double placentae, without valves ; 

 in Eschscholtzia there are two valves with placentae and stigmata, and two 

 stigmata without valves or placentae. But suppose that the two valves of 

 Cruciferae had stigmata, as they should have (and a tendency to produce 

 which actually exists in Iberis umbellata), and that the two stigmata of 

 Eschscholtzia had valves, as would be regular, what would then be the dif- 

 ference between the two ? it would be reduced to nearly this, that in "Esch- 

 scholtzia the two placentiferous pieces would occupy the greater part of the 

 pericarpium, the two sterile valves being very small; v?hile in Cruciferae 

 the two placentiferous pieces would be very small, the chief part of the 

 pericarpium being occupied by the sterile valves. To make this more 

 apparent, let the following figures represent an imaginary section of the 



fruit of both Cruciferae and Eschscholtzia : — 



