88 



ME, C. DABWIS 0>' THE DIMOKPHIC CO>'DITIO:S 





Number of Ufumber 

 flowers of good 

 fertilized. poda. 



Weight of. 

 seed in ; 

 grains. 



Number 

 of good 

 podg. 



Weight of 

 seed in 

 grains. 



The two homomorphic 1 

 unions j 



The two heteromor- \ 

 phic unions J 



100 

 100 



63 



75 



25 



48 



100 

 100 



40 

 64 



In the first part of the xipper table, the number of flowers fer- 

 tilized and the simple result is shown ; and at the right hand, for 

 the sake of comparison, the calculated product of the weight of seed 

 from 100 good pods of each of the four unions is given ; showing 

 that in each case the heteromorphic union is more fertile than the 

 homomorphic union. Beneath we have a simple summary of the 

 two homomorphic and the two heteromorphic unions. And lastly, 

 for the sake of comparison, a calculation has been made from this 

 summary ; first, assuming that 100 flowers of both kinds of unions 

 were fertilized ; and then to the right hand, assuming that 100 

 good pods were produced from both unions. If we compare the 

 result, we see that the flowers of the two heteromorphic unions 

 produced a greater number of good pods, and a greater weight of 

 seed, than the flowers of the two homomorphic unions ; and again 

 (and this is the fairest element of comparison, for accidents are 

 thus almost eliminated), that the good pods from the two hetero- 

 morphic unions yielded more seed, in about the proportion of three 

 to two, than those from the two homomorphic unions. The dif- 

 ference in weight from 100 capsules of the two forms is 24 grains, 

 and this is equal to at least 1200 seeds. 



Beneath we have Table 11. of P. veris, or the Cowslip. The 

 upper part is exactly the same as in the Table of P. Sinensis, and 

 we see ia each case that the heteromorphic is more fertile than 

 the homomorphic union. The calculated results irom the sum- 

 mary of the two homomorphic and the two heteromorphic unions 

 are more complex than with the last species, as I wished to show 

 that, however we proceed, the general result is the same. We see 

 that the assumed hundred flowers, heteromorphically fertilized by 

 the pollen of the other forms, yielded more capsules, more good 

 capsules, and a greater weight of seed ; but I rely little on this, as 

 some whole umbels perished after being fertilized. The fairest 

 element of comparison is to take the good capsules alone ; and we 

 here see that tlie 100 from the two heteromorphic unions yielded 

 seed which in weight was as 54 to 35 from the 100 good capsules 



