46 



Effects of Alcohol on Selenia bilimaria 



As before, instead of rearing all the larvae, a random sample of fifty 

 ova was chosen from each batch, and the resulting larvae fed up on haw- 

 thorn, the food plant of the parents. Unlike them, however, the three 

 sets were reared in well-ventilated and well-lighted cages such as are 

 employed in normal breeding operations. In the first four instars no 

 deaths occurred in the crossings in which treated insects took part ; 

 even in the inbreeding of the controls the loss was small, the deaths in 

 each skin being one, three, none, and four respectively. 



When, however, the first larvae were ready to spin, these being 

 derived from a pairing between a treated male and an untreated female, 

 there were left fifty of that cross, forty-six of the reverse brood and 

 thirty from the controls. In view of the fact that very great differences 

 in speed of feeding up were now most strikingly displayed, it will be 

 best to show the numbers spinning up and pupating each day in the 

 form of a tabular diary. In this table (Table V) records are set out 

 daily until August 22nd, when all of the earliest lot had spun, and for 

 two day intervals subsequent to that. 



TABLE V. 



Alcoholised Malus 



Control Males 



Control Males 



Control Females Alcoholised Females Control Females 



Date 



August 8th 



August 9th 



August 10th 



August 11th 

 August 12th 

 August 13th 

 August 14th 

 August 15th 

 August 16th 



August 17th 



August 18th 

 August 19th 



August 20th 



August 21st 

 August 22nd 

 August 23rd— 25th 

 August 25th— 27th 

 August 27th— 29th 

 August 29th— 31st 

 August 31st — September 2nd 

 September 2nd — 4th ... 

 September 4th — 6th 

 September 6th — 8th 



Spun Pupated Spun Pupated Si^un Pupated 



5 1 — — _ _ 



11 2 5 _ _ — 



15 5 7 3 — — 



21 12 10 6 1 — 



25 15 11 8 1 — 



31 21 13 10 2 1 



37 26 17 11 4 1 



40 32 18 13 6 2 



42 37 20 17 7 4 



44 40 22 18 9 5 



46 42 25 20 10 8 



50 44 28 21 14 9 



50 46 28 24 15 10 



50 50 30 27 17 14 



50 50 30 28 19 17 



50 50 32 30 23 20 



50 50 32 30 24 21 



50 50 36 32 25 21 



50 50 37 32 25 24 



50 50 41 36 25 25 



50 50 41 41 28 26 



50 50 41 41 28 27 



From the above figures it is very clear that the total loss in the 

 cross between an alcoholised male and a control female is zero, that in 

 the reciprocal cross is nine ( = 18°/^), and amongst the controls twenty- 



