310 Mr. Poulton's notes in 1886 



9. The comparatively late emergence of female 

 moths from the pupa. — Every entomologist who has 

 bred lepidopterous insects in the hope of pairing them 

 in order to obtain eggs must have noticed that the great 

 difficulty with which he has to contend is the fact that 

 the males tend to emerge before the females. I have 

 noticed this for several years, and in the case of all the 

 species which I have employed in large numbers, and I 

 know that others have had a similar experience. At 

 first sight it would appear that this want of uniformity 

 must be a disadvantage to the species, for large numbers 

 of males must die before the females appear, and during 

 the time when the latter are only beginning to emerge 

 in small numbers. But, on the other hand, a more 

 than compensating advantage is doubtless gained by 

 the complete rivalry among a large number of males for 

 each of the females as they emerge, so that in the 

 majority of cases success in courtship is gained through 

 the possession of qualities which are of advantage to 

 the species, and not merely through the circumstance of 

 emergence at an appropriate time. 



10. The hereditary transmission of pink tubercles 

 on the larv^ of Saturnia carpini. — The following 

 notes I owe almost entirely to the kindness of my friend 

 Dr. F. A. Dixey. On July 25th, 1885, eighty larvae of 

 this species were sent to Dr. Dixey from Norfolk, where 

 they had been found feeding on meadow-sweet. The 

 larvae were mostly in the last stage, or the last but one, 

 and after their arrival in Oxford they were fed upon 

 willow. The ground colour of these in the last stage 

 but one, whenever observed, was of a light bright green, 

 but in the last stage it varied from this colour to a dull 

 and dusky green. The black markings were also very 

 variable in the last stage, being, as a rule, especially 

 small in the bright green larvae. In some larvae the 

 black rings were incomplete, and were occasionally 

 reduced to a mere black line round each tubercle. The 

 longitudinal black marks, as a rule, only occurred in 

 the dull green larvae. In seventy-six larvae the tubercles 

 were yellow, varying from orange to lemon-yellow, and 

 the lighter tubercles were generally found upon the 

 bright green larvae. In three larvae the tubercles were 

 pink, without a trace of yellow or orange ; in one the 



