1984] 
Rut ow ski — Pier is protodice 
151 
after mating. This suggests that a female’s supply of secretions but 
not sperm is effectively depleted beginning at about six days after 
mating. Suzuki (1979) examined the phenomenon of multiple 
mating in Pier is rapae L., a close relative of P. protodice, and found 
that most females mate for the second time about 6 to 8 days after 
being released as a virgin in the field. These data support Suzuki’s 
hypothesis that Pieris females may multiply mate to gain nutrients 
in that they appear to be doing so at a time when their supply of 
secretions from previous matings is largely depleted. This hypothe- 
sis is also confirmed by the data from the dissections of field- 
collected females in which at least one of the spermatophores 
carried by twice-mated females was often small and greatly depleted. 
Summary 
This study examines the production and use of secretions passed 
by a male during copulation to a female in the checkered white 
butterfly ( Pieris protodice). Males pass about 7 to 8 percent of their 
body weight at copulation in the form of secretions deposited in the 
female’s reproductive tract. No correlation between the quantity of 
material passed and male size was found. However, it was found 
that the proportion of male body mass passed was inversely 
correlated with body mass suggesting that all males, regardless of 
size pass a typical quantity of material. A mating depletes the 
material a male has for subsequent mating but only temporarily. 
Males were found to have mostly recovered their potency in 24 hrs, 
even without food or water between matings. 
Females have mostly depleted the material received from males in 
about 5 to 7 days. In the field females carrying multiple sperm- 
atophores always had one that was greatly depleted indicating that 
they remate only when material from a previous mating was 
depleted. The results are compared to information on the use and 
production of male-imparted secretions and mating behavior in 
other butterflies. 
Acknowledgements 
I thank John Schaefer and Scott Snead for their assistance in the 
field and laboratory. Financial support was provided by National 
Science Foundation Grants BNS 80-14120 and BNS 83-00317. 
