64 



The number of spécimens collected amounted tu 15, 8, 

 13, 6 and 2 in the same order as the dates. Ail thèse 

 fruits hâve been carefully examined and hâve furnished 

 only one réceptacle of which the top was dichotomous. 

 As is shown in fig. 1, which represents this torus slightly 

 magnified (the edible part of the fruit having been removed) 

 the whole surface was covered with carpels and could 

 not hâve been anything but an entire thalamus growing 

 in two directions. The number of carpels amounted to 

 150, whereas the ordinary number seems not to exceed 

 100. The calyx is made up of six sepals, a fact note- 

 worthy in itself, since it shows augmentation also in this 

 respect. On the other hand there were 40 spécimens pos- 

 sessing quite simple réceptacles and showing not even a 

 trace of doubling. 



From thèse facts we are entitled to _ 



argue that a really dichotomous torus 

 is a thing of very rare occurrence and 

 cannot possibly account for the great 

 number of raspberries which in 1906 

 and 1907 and in a less degree in 1908 

 hâve been produced in the „Proeftuin". 

 The characterlstics of a subséquent 

 splitting up of the torus (fig. 2), in 

 which also the peduncle often takes 

 part, are so very différent from those 

 in fig. 1 that additional proof seems 

 superfluous. 



The only question is: at what time 

 and under what conditions does the 

 splitting of the réceptacle take place? 

 I hâve not, indeed, observed the actual 

 moment of splitting but should think -*' 

 that it must coïncide with the stage of Fig. 2. 



Fig. 1. 



