H. E. Crampton 
127 
although the females are more variable in the absolute bust measures of length 
and depth, the other sex is more variable in the significant proportions of the bust. 
The lower value of the coefficients relating to the antennal characters of the males 
is extremely suggestive, I think, in view of the function which these organs 
perform during iinaginal existence. It is now well known, owing particularly to 
TABLE X. 
The Coefficients of Variability of Male and Female Pupal Characters. 
Character 
All. 
Males Females 
Survivors. 
Males Females 
Perfect Survivors. 
Males Females 
Length 
Weight 
4-38 4-20 
12-43 11-59 
4-45 4-90 
14-65 12-21 
Bust, Length 
„ Width 
„ Depth 
„ Frontal Proportions 
,, Sagittal ,, 
4- 21 4-'23 
5- 14 4-92 
4-46 4-57 
4- 12 3-61 
3-16 2-86 
4- 25 3-66 
5- 07 4-35 
4-34 4-12 
3-79 2-90 
3-14 2-61 
3- 83 3-95 
5-03 4-66 
4- 16 4-S7 
3-69 2-88 
3-00 2-61 
Left Antenna, Length ... 
Width ... 
„ „ Proportions 
4- 91 4-90 
5- 95 5-43 
5-26 5-20 
4- 12 4-09 
5- 15 4-66 
4-93 5-30 
3- 84 4-25 
4- 63 4-80 
4-80 5-47 
the recent work of A. G. Mayer, that the male moth is guided by its sensory 
antennary organs in finding the female. It is decidedly interesting to find these 
organs are less variable in the sex for which tliey are the more useful. 
VI. Discussion and Conclusion. 
The facts recorded in the foregoing account relate to eight or to ten characters 
of the pupae of one species of Saturnid moth for one winter season. It is obvious 
that it would be futile to discuss the bearing of these facts upon the wide question 
of evolution in any extended form, until the figures here given may be supplemented 
by others relating to the same and other species of moths, obtained by more 
detailed studies upon the same and related questions in more abundant material. 
It is nevertheless necessary to deal briefly with certain aspects of the evidence 
which has been offered, in order to avoid misconception regarding the main 
conclusion stated, namely, that there is a real relation between the process of 
elimination in pupae, and the extent and character of their variation. It may be 
stated here, that the results of later studies have in no essential way altered the 
point of view which was arrived at from the consideration of the results of the 
initial investigation, here recorded. 
