534 Harris: ihe fruit of Opuntia 



bearing 



Those who have had much experience with teratological material, 

 however, will be exceedingly cautious in attaching the significance 

 which Professor Tourney does to the one enlarged pistil contain- 

 ing seeds and which has assumed the color of a fruit. Further- 

 more it hardly need be pointed out that the derivation of a portion 

 of the inferior ovary from the receptacle of the flower, a structure 

 caulome in nature, removes* the necessity of accounting for the 

 structure of the fruit by assuming that the ovary has receded into 



a vegetative branch. 



We may examine a few of the published discussions 



upon this point. 



Ramirez * has published descriptions and excellent colored 

 plates of three malformations in the fruits of Opuntia. After a 

 considerable discussion of the morphological nature of the inferior 

 ovary he takes up the three deviations observed. 



The first case, as he describes it, is one of fusion, consisting of 

 a cladode, or joint of the shoot, bearing at the tip a mature red 

 fruit which, instead of being articulated with the stem as is ordi- 

 narily the case, is continuous with it, the two regions being sepa- 

 rated merely by a slight constriction of a whitish instead of green 

 or red color ; the whorls of spines and the cushions which they 



subtend are continuous in the two portions of the structure under 

 consideration. 



The second case is one designated as the inclusion of a fruit in 

 a cladode which is somewhat thicker in the middle and on one 

 side, but except for this and the presence of the scar at the apex 

 and the more or less normal ovary inside closely resembles one of 

 the familiar vegetative joints. 



The third case is one of "lateral proliferation of the fruit" in 

 which a large number of fully developed fruits are borne upon the 

 side of another. 



The interpretation which Ramirez has to suggest for these 

 anomalies has, it seems to me, much to commend it. He consid- 

 ers that the ovaries originate in a normal manner, but that in cer- 

 tain regions they undergo a slight modification and that, due to the 

 hereditary tendency of Opuntia to form cladodes, .the ovary is more 

 or less completely transformed into structures resembling the 



* Ramirez, J. Anales Inst. Med. Nac. 3 : 223-227. //. j-7. 1897. 



