167 



note is to put on record the results of a couple of series of weigh- 

 ings which seem of interest in this connection. 



The pods of the American bladder nut, Staphylea trifolia, are 

 characterized by the production of few seeds. In a large series 

 of countings it will be found that the great majority of fruits 

 produce one or two seeds only; those with more than six are 

 very rare. This is shown in Table II. for 4,024 fruits collected 



Table II 



Total Seeds per 

 Fruit 



Number of Fruits 



Total Seeds per Fruit 



Number of Fruits 







4 



8 



16 



I 



1.585 



9 



9 



2 



1,240 



10 



5 



3 



637 



II 



2 



4 



310 



12 



I 



5 



125 



13 



— 



6 



59 



14 



— 



7 



30 



15 



I 



from eleven shrubs in the North American Tract of the Missouri 

 Botanical Garden in the fall of 1905. The polygon is very skew, 

 the pronounced mode being a single seed while the frequencies 

 fall off rapidly as the number of seeds become larger. In the 

 collections from individual shrubs the empirical mode is some- 

 times on two instead of one, but the conspicuous skewness is a 

 feature of all of the several series of Staphylea fruits hitherto 

 examined. The same skewness is observed in Table III. for 

 number of seeds per locule (of which there are three per fruit). 





Table III 





Seeds per Locule 



Number of Locules 



Seeds per Locule 



Number of Locules 







I 

 2 



3 



5-684 



4.593 



1.387 



313 



4 

 5 

 6 



72 



19 



4 



I have been able to study fruits from only a single tree of the 

 yellow wood, Cladrastis tinctoria, in the Arboretum of the Mis- 

 souri Botanical Garden. Possibly because of its isolation, the 

 fruiting of this individual is not typical of the species, but in 



