128 OUTLINES OF ENTOMOLOGY. 



The Hellgrammite fly and the other, much smaller, species of, the 

 family SCIALIDJE have carnivorous larvae that live under stones in run- 

 ning water. The large fly above named (Corydalis cornutusj is the 

 only conspicuous member of the group. This is one of the largest, if 

 not the very largest, insect in the Order the length being between 

 two and three inches, with a wing expanse of about five inches. It is 

 quite common in most sections of the United States. The body is 

 soft, with the pro-thoracic joint rather narrow, forming a sort of neck 

 to which the much broader and rather square head is closely joined. 

 The eyes are rather small and wide apart, and the stout, many-jointed 

 antennae taper to a point. In the female the jaws are broad, curved 

 and notched at the extremity, but in the male these are modified into 

 a pair of long, cylindrical tapering tusks, with which he can clasp the 

 neck of the female. The wings are quite broad, of rather thick mem- 

 brane, with a fine net-work of veins, and stippled all over with whitish 

 dots. The general color of the insect is a dull, ash gray. The female 

 lays her eggs on sticks or leaves or stones that overhang the water, 

 protecting and surrounding them by a white substance that gives the 

 entire mass the appearance of a splash of whitewash. The larvae, upon 

 hatching, drop into the water. They are formidable- looking creatures 

 when full grown. The head is broad and almost square, with strong 

 jaws and other mouth parts. The thoracic joints, of which the first 

 is longest, are quite elegantly sculptured. The feet terminate in a pair 

 of claws. The sides of the hind body are furnished on each joint 

 with spiny, oar-like processes and feathery tufts for gills, and there 

 are also spiracles through which air can be breathed. They are 

 from two to two and a half inches long by nearly one-half inch in 

 diameter. They are highly esteemed for bait by fishermen, by whom 

 they are termed "crawlers," "dobson," etc. It is said that they are 

 nearly three years in completing their growth, and that the transfor- 

 mations are rapid and take place in cells under stones or drift-wood on 

 or near the banks of the stream. 



The other insects of this group (genera Chauliodes and SialisJ 

 bear a close general resemblance to Corydalis m structure and habit, 

 but are very much smaller and do not attract much popular attention. 



Among the PSEUDONEUROPTERA the most conspicuous and 

 beautiful insects are the Dragon flies or Mosquito-hawks ( LIBELLU- 

 LID^:). These are also called " Darning needles," and have been made 

 objects of terror to children by the tradition that they are constantly 

 watching for an opportunity to u sew up their ears, ?f or do them some 

 other bodily harm. In other parts of the country they are termed 

 " Snake doctors," and are said to hover over the bodies of dead reptiles 



