CHAP. III. 



SAL VI A COCCINEA. 



93 



IV. LABIATES. SAL vi A COCOINKA.* 



This specias, unlike most of the others in the same genus, 

 yields a good many seeds when insects are excluded. I gathered 

 ninety-eight capsules produced by flowers spontaneously self- 

 fertilised under a net, and they contained on an average 1*45 

 seeds, whilst flowers artificially fertilised with their own pollen, 

 in which case the stigma will have received plenty of pollen, 

 yielded on an average 3 '3 seeds, or more than twice as many. 

 Twenty flowers were crossed with pollen from a distinct plant, 

 and twenty-six were self-fertilised. There was no great difference 

 in the proportional number of flowers which produced capsules 

 by these two processes, or in the number of the contained seeds 

 or in the weight of an equal number of seeds. 



Seeds of both kinds were sown rather thickly on opposite sides 

 of three pots. When the seedlings were about 3 inches in 

 height, the crossed showed a slight advantage over the self- 

 fertilised. When two-thirds grown, the two tallest plants on 

 each side of each pot were measured ; the crossed averaged 16 37 

 inches, and the self-fertilised 11 '75 in height; or as 100 to 71. 

 When the plants were fully grown and had done flowering, the 

 two tallest plants on each side were again measured, with the 

 results shown in the following table : 



TABLE XXVII. 



* The admirable mechanical 

 adaptations in this genus for 

 favouring or ensuring cross-ferti- 

 liation, have been fully described 



by Sprengel, Hildebrand, Delpino, 

 H. Muller, Ogle, and others, in 

 their several works. 



