68 MIMULUS LUTEUS. Chap. III. 



crossed and self-fertilised plants of the last generation ; but 

 neither my gardener nor myself could remember any such variety 

 in the seedlings raised from the purchased seed. It must there- 

 fore have arisen either through ordinary variation, or, judging 

 from its appearance amongst both the crossed and self-fertilised 

 plants, more probably through reversion to a formerly existing 

 variety. 



In Pot I. the tallest crossed plant was 85 inches, and the 

 tallest self-fertilised 5 inches in height. In Pot II. the tallest 

 crossed plant was 65 inches, and the tallest self-fertilised plant, 

 which consisted of the white variety, 7 inches in height ; and 

 this was the first instance in my experiments on Mimulus in 

 which the tallest self-fertilised plant exceeded the tallest crossed. 

 Nevertheless, the two tallest crossed plants taken together were 

 to the two tallest self-fertilised plants in height as 100 to 80. 

 As yet the crossed plants were superior to the self-fertilised in 

 fertility ; for twelve flowers on the crossed plants were crossed 

 and yielded ten capsules, the seeds of which weighed 1 -71 grain. 

 Twenty flowers on the self-fertilised plants were self-fertilised, 

 and produced fifteen capsules, all appearing poor ; and the seeds 

 from ten of them weighed only -68 grain, so that from an 

 equal number of capsules the crossed seeds were to the self- 

 fertilised in weight as 100 to 40. 



Crossed and self-fertilised Plants of the Fifth Generation. Seeds 

 from both lots of the fourth generation, fertilised in the usual 

 manner, were sown on opposite sides of three pots. When the 

 seedlings flowered, most of the self-fertilised plants were found 

 to consist of the tall white variety. Several of the crossed plants 

 in Pot I. likewise belonged to this variety, as did a very few in 

 Pots II. and III. The tallest crossed plant in Pot I. was 7 inches, 

 and the tallest self-fertilised plant on the opposite side 8 inches ; 

 in Pots II. and III. the tallest crossed were 4 and 5i, and the 

 tallest self-fertilised 7 and 6j inches in height; so that the 

 average height of the tallest plants in the two lots was as 100 

 for the crossed to 126 for the self-fertilised; and thus we have 

 a complete reversal of what occurred in the four previous gene- 

 rations. Nevertheless, in all three pots the crossed plants 

 retained their habit of flowering before the self-fertilised. The 

 plants were unhealthy from being crowded and from the extreme 

 heat of the season, and were in consequence more or less 

 Bterile ; but the crossed plants were somewhat less sterile than 

 the self-fertilised plants. 



