66 CARPELS [CH. VII 



is thus composed of coherent carpels, it is described as a 

 syncarpous ovary (Fig. 21). 



To illustrate this, it is permissible to employ an 

 analogy which, while not strictly true in point of fact 

 as regards the mode of development, is sufficiently so for 

 the purpose, provided the student does not push it farther 

 than the case demands. If we suppose the carpel to be 

 a folded leaf (and it is homologous with such an organ), 

 then a pea-pod consists of one such leaf, the margins 

 of which are conjoined, and bear the ovules the young 

 peas or the incipient seeds : the opposite edge of the pod 

 corresponds to the midrib of the leaf, and the inside 

 surface of the pod corresponds to the upper side of the 

 leaf, supposing it expanded. 



Now let us imagine two carpels, like pea-pods, to 

 arise in the centre of the flower, so placed that their 

 pea-bearing margins face the centre of the flower and 

 cohere, not margin to margin of the same pea-pod, but 

 the margin of the one pod to the margin on the same 

 side of the opposite pod : this would give a larger pod-like 

 box, but composed of two coherent carpels, instead of 

 one. Obviously the syncarpous ovary may be composed 

 similarly of three, four, or more such coherent carpels 

 (Fig. 21). 



The above illustrative cases are realised in Willows 

 and Poplars, Corydalis, Esclischoltzia, Glaucium, Capparis, 

 Saxifrages, Gentians, where we find two carpels coherent ; 

 in Violets, Reseda, and Juncus, some Ochnaceae, Helian- 

 themum, there are three ; in Parnassia and some Poppies 

 there are four; in Cistus, five, and in many Poppies 

 numerous carpels occur. Here, again, cases are known of 

 the nature of branching, but they concern us very little 

 or not at all. 



