208 
Psyche 
[Vol. 88 
sound, the female might sooner visually detect and be able to 
evaluate the male as a prospective mate, and thus sooner choose to 
wait for or flee from him. The advantages gained by the male by 
increasing his communicatory distance might be: 1) alerting a 
receptive female to his presence at a greater distance, possibly 
causing her to remain in the vicinity for a longer period of time (and 
perhaps inhibiting her predatory instincts), so that the male has a 
greater chance of finding and courting her; 2) based on many 
observations of P. mystaceus and of other Phidippus species, non- 
receptive females usually avoid advancing males; thus, by alerting a 
female to his presence at a greater distance, a male would reduce the 
chance of stimulating an aggressive response by a non-receptive 
female. 
As evidence for these probable advantages, analysis of courtships 
showed that the male began courting a female from 2-4 times 
further away when unconfined (on the live-oak branch) than did 
other species of Phidippus when observed under unconfined experi- 
mental conditions (Edwards, 1975). At the greater distances, only 
sound was used initially by a P. mystaceus male upon sighting a 
female, indicating that this form of communication was important 
in alerting a female to his presence. Sound was also used alternately 
with palpal exploration of the silk when the male was in contact 
with the female’s draglines in the petri dish, even though she was not 
visible. Under natural conditions, a male likely would often en- 
counter a female’s dragline prior to locating her; he could maximize 
his chances of mating by beginning to signal immediately, regardless 
of whether or not the female was visible to him. 
Components of Behavior and Morphology 
The male’s initial palpal exploration of the female’s silk draglines 
and nests has been noted for other salticids (Richman, 1977). The 
presence of a contact pheromone on the silk could indicate to a male 
that a female was, or had been, in the vicinity. Contact pheromones 
(Hegdekar and Dondale, 1969) and dragline following by males 
(Tietjen and Rovner, 1980) have been demonstrated for some 
lycosids, but have not yet been conclusively demonstrated for any 
salticid. Foelix (1970) demonstrated the presence of chemosensitive 
setae in certain araneid spiders and hypothesized that those setae 
were contact chemoreceptors. He showed that the suspected chemo- 
