144 
Psyche 
[Vol. 91 
Table 1. Summary of 28 copulations that lasted 60 min or less. 
Variable (units) 
Mean 
Standard 
deviation 
Sample 
size 
Range 
Male forewing length (mm) 
23.9 
1.1 
28 
21-26 
Estimate of male precopulatory 
body mass (mg) 
52.9 
10.9 
26 
29.1-70 
Female forewing length (mm) 
23.3 
1.49 
28 
19-26 
Copulation dura- 
tion (min) 
31.7 
9.23 
26 
22-60 
Volume of male-imparted 
secretions (/u) 
3.44 
1.08 
28 
1.36-5.46 
Mass of male-imparted 
secretions (mg) 
3.89 
1.15 
28 
1.78-5.9 
% of male body mass passed 
7.88 
2.59 
26 
2.7-12.7 
tendency in copulations lasting an hour or less for females to receive 
smaller quantities of material than in long copulations. 
Female forewing length was not significantly correlated with male 
forewing length (r= -0.0404, n=28, p=0.42) which suggests size 
assortative mating does not occur in this species. Female forewing 
length was not significantly correlated with the volume of secretions 
received (r=-0.25, n=28, p=0.10) or the mass of secretions received 
(r=0.228, n=26, p=0.122). Female size apparently does not in- 
fluence the quantity of material passed. 
Ten males were mated and then successfully remated 24 hours 
later. Table 2 summarizes a comparison of first and second matings 
by these males. Statistical comparisons reveal that significantly less 
material was passed in the second matings (t = 4.32, 9 df, p<0.002) 
and males passed a significantly smaller proportion of their body 
mass (t=3.3, 9 df, p<0.01). Although not all copulation durations 
were precisely measured, those that were displayed no difference 
between the durations of first and second matings separated by 24 
hrs (t = 0. 1 07, 15 df, p=0.46). 
Rate of use of male secretions by female 
Fig. 4 shows the mass of material remaining in the females’s 
reproductive tract at various times after mating. During the first day 
or two after copulation little material has left the bursa copulatrix 
but then the decline is rapid until day 5 at which point it seems to 
level off. The correlation between days since copulation and ma- 
terial left in the bursa copulatrix was negative and highly significant 
(r=— 0.751, n = 46, p<10" 8 ). 
