CHAP. IV. PAPAVER VAGUM. 107 



having died) 15 '51, or as 100 to 89. I am surprised that the 

 difference did not prove somewhat greater, considering that in 

 the last experiment it was as 100 to 86; but this latter ratio, as 

 before explained, was probably too great. It should, however, 

 be observed that in the last experiment (Table XXXI.), the 

 crossed plants competed with plants of the third self-fertilised 

 generation ; whilst in the present case, plants derived from a 

 cross with a fresh stock competed with self-fertilised plants of 

 the first generation. 



The crossed plants in the present case, as in the last, were 

 more fertile than the self-fertilised, both lots being left un- 

 covered in the greenhouse. The thirty crossed plants produced 

 103 seed-bearing flower-heads, as well as some heads which 

 yielded no seeds ; whereas the twenty-nine self-fertilised plants 

 produced only 81 seed-bearing heads; therefore thirty such 

 plants would have produced 83*7 heads. We thus get the 

 ratio of 100 to 81, for the number of seed-bearing flower-heads 

 produced by the crossed and self-fertilised plants. Moreover, a 

 number of seed-bearing heads from the crossed plants, com- 

 pared with the same number from the self-fertilised, yielded 

 seeds by weight, in the ratio of 100 to 92. Combining these 

 two elements, viz., the number of seed-bearing heads and the 

 weight of seeds in each head, the productiveness of the crossed 

 to the self-fertilised plants was as 100 to 75. 



The crossed and self-fertilised seeds, which remained after 

 the above pairs had been planted, (some in a state of germina- 

 tion and some not so), were sown early in the year out of doors 

 in two rows. Many of the self-fertilised seedlings suffered 

 greatly, and a much larger number of them perished than of 

 the crossed. In the autumn the surviving self-fertilised plants 

 were plainly less well-grown than the crossed plants. 



VII. PAPAVEBACE.E. PAPAVEB VAGUM. 



A sub-species of P. dub I urn, from the south of Frame. 

 The poppy does not secrete nectar, but the flowers are highly 

 conspicuous and are visited by many pollen-collecting bees, 

 flies and beetles. The anthers shed their pollen very early, and 

 in the case of P. rhaas, it falls on the circumference of the 

 radiating stigmas, so that this species must often be self-ferti- 

 lised; but with P. dubium the same result does not follow 

 (according to H. Muller, ' Die Befruchtung,' p. 128), owing to 



