1973] 
Robinson — Cryptic Postures 
165 
Neither of the insects showed any of the forms of secondary de- 
fense that Robinson (1969a) suggested were consequences of escape- 
inhibiting cryptic postures. Both postures could be regarded as in- 
hibiting the possibility of immediate escape following the penetration 
of the first line of defense. Thus in the Phyllophora position the 
jumping legs are in such a position that immediate escape by jump- 
ing is not possible although the animal can push itself off the sub- 
strate and drop. Similarly with Acauloplacella. Despite this neither 
animal had a startle display, chemical secretion or was armed with 
defensive spines. 
Many of the orthopteroid insects that occur in this region of 
New Guinea have complex secondary defenses and in particular use 
strong spines in defense. This may be correlated with the fact that 
most of the mammalian predators of insects (marsupials) are noc- 
turnal and handle their prey. They may thus be less susceptible to 
visual defenses and more affected by mechanical counter-attack. 
References 
Chopard, L. 
1938. La biologie des Orthopteres. Paris: Lechavalier. 
Cott, H. B. 
1940. Adaptive coloration in animals . London: Methuen. 
Edmunds, M. 
1972. Defensive behaviour in Ghanian praying mantids. Zool. Journal 
Linnean Soc. London. 51:1-32. 
Robinson, M. H. 
1968. The defensive behavior of Pterinoxylus spinulosus Redtenbacher, 
a winged stick insect from Panama. Psyche. 75: 195-207. 
1969a. The defensive behaviour of some orthopteroid insects from Pan- 
ama. Trans. Royal Entomological Soc. London. 121: 281-303. 
1969b. Defenses against visually hunting predators. In Dobzhansky 
et al. Evolutionary Biology. 3 : 225-259. 
1973. Insect anti-predator adaptations and the behavior of predatory 
primates. Actas del IV Congresso Latinamericano de Zoologia 
II. 811-836. 
Ruiter, L. de. 
1952. Some experiments on the camouflage of stick caterpillars. Be- 
haviour. 4: 222-232. 
