Harris : The fruit of Ofuntia 635 



4 



joints of the stem. It will be seen that the nomenclature used by 

 Ramirez Is not in accord with his explanation, a point of minor 

 importance, however. The second case described by Ramirez, 

 and the one upon which he largely bases his interpretation of the 

 first two cases described, is clearly identical with that illustrated 

 by Tourney (Jig's, ii and 12) as occurring in O. Eugelvtanni as 

 well as a number of other species. 



The fruit of OpJiutia Ficns4ndica^ ** wholly enclosed in one of 

 the well-known flat branches of this plant,'* described and figured 

 by Ernst,* is In all probability identical with the forms figured by 

 Ramirez and Tourney. Masters f supposes that this case is analo- 

 gous to the fruit of Cerctis described by Zuccarini. 



This brings us to the consideration of certain interesting anom- 

 alies in Cere7is. In this genus the flowers are normally lateral but 

 occasionally those w^hich are terminal have been observed, as in C, 

 azureus^ C. caendescens^ C. serpentimis^ C. speciosissimus and C 



splendiihis. 



Penzig in his Pflanzenteratologie remarks that when the flowers 

 occupy a terminal position, '• sie sind dann meist mehr oder min- 

 der tief in die Sprossspitze eingesenkt." 



The figures which I have examined represent the flower or 

 the fruit as produced directly from the apex of the main axis. 

 Particularly interesting are the description and figure given by 

 Zuccarini, J in which a longitudinal section representing the course 

 of the vascular bundles is shown. 



In the large collection of succulents at the Missouri Botan- 

 ical Garden I have been able to examine several of the cases 

 which have been described in the literature, and Mr. Thompson 

 called my attention to a large specimen of C. baxanicnsis with sev- 

 eral terminal fruits, one of which had other flowers developing 

 from the side. A section of one of these fruits showed it to be 

 sterile. In these cases the meristematic region of the stem prob- 

 ably gave rise immediately to floral organs instead of continuing 

 its growth as a vegetative shoot ; this has given rise to the impres- 

 sion that the flower or fruit is sunken in the tip of the axis. This 

 explanation may perhaps also apply in some cases to the fruits o^ 



* Ernst, A. Nature 27 : 77- ^^"^1^ 



t Masters, M. T. Nature 27: 126. i88j. 



: Zuccarini, J. G. Abli. Akad. Wiss, Mlinchen 4I : 155-161. //. /--?. 1844. 



