234 Nerve-winged Insects; Scorpion-flies; Caddis-flies 
concealed in sheltered places. They are active, though, when disturbed, and 
look much like the larvae, but are more robust-bodied and bear externally 
the developing wings. The head, with eyes and antennae, is more like that 
of the adult. The complete metamorphosis of these insects seems very 
simple compared with that of such other holometabolous insects as house¬ 
flies and honey-bees. The adult female (Fig. 324) has a long, slender, 
curved, pointed ovipositor, which probably is used to deposit the eggs in 
deep, narrow, and safe cracks in the bark. But the oviposition has not 
yet been seen, and the full life-history of the Raphidians has yet to be worked 
out. 
The extraordinary-looking insect shown in Fig. 325 is one of the few 
members of the Mantispidae, the sixth family of the Neuroptera. Its great 
spiny, grasping fore legs and its long neck make it resemble its namesake, 
the praying-mantis of the order Orthoptera, but its four membranous, net- 
veined wings show its affinities with the Neuroptera. The fore legs are like 
those of the mantis because Mantispa has similar habits of catching live 
prey with them: it is a case of what is called by biologists “parallelism of 
structure,” by which is meant that certain parts of two animals become 
developed or specialized along similar lines, not because of a near relation¬ 
ship between them, but because of the 
adoption of similar habits. The wings of 
bats and those of birds show a general 
parallelism of structure, although bats and 
birds belong to two distinct great groups 
of animals. 
Only two genera, viz., Mantispa and 
Symphasis, of Mantispidae are known, and 
these include but five American species. 
Symphasis signata (Fig. 325) is found in 
California, while of the four species of Man¬ 
tispa three are found in the East and South, while one ranges clear across the 
continent. But they are insects only infrequently seen, and each captured 
specimen is a prize. The life-history of no one of our species has been studied— 
an opportunity for some amateur to make interesting and needed observations 
—but Brauer has traced the life of the European species, Mantispa styriaca, 
and found it of unusual and extremely interesting character. The following 
account of Brauer’s observations is quoted from Sharp (Cambridge Natural 
History, vol. v): “The eggs are numerous but very small, and are deposited 
in such a manner that each is borne by a long slender stalk, as in the lace¬ 
wing flies. The larvae are hatched in autumn; they then hibernate and 
go for about seven months before they take any food. In the spring, when 
the spiders of the genus Lycosa have formed their bags of eggs, the minute 
Fig. 325 .—Symphasis signata. (One 
and one-half times natural size.) 
