62 CATERPILLARS AND THEIR MOTHS 



"the country " and to know "all about" them. They 

 make capital hunters, too, and to their sharp eyes we 

 owe many valuable caterpillars and moths. It makes 

 their summer much more interesting to look for speci- 

 mens, and them much happier to feel that they are 

 really helping some one. At first they will doubtless 

 bring in creatures one does not care to have, the saw- 

 fly larva, Cim'hex amerlca'na, for instance, which 

 abounds on elm, willow, hazel, alder, and other plants. 

 It may be white, yellow, salmon-pink, or green, with 

 two narrow black dorsal lines and twenty-two legs. 

 It belongs to the hymenopterous family Tentlire- 

 din'ldcp, a family whose larvae do much damage by de- 

 foliating trees of various kinds. The flies are called 

 saw-flies, because the abdomen of the female has a 

 pair of saws witli which she saws slits in the stems or 

 leaves of plants, and in the slits lays her eggs. The 

 larvae are not true caterpillars, but have a pair of pro- 

 legs on almost every segment of the abdomen, while 

 but one family of true caterpillars has more than ten 

 abdominal props. Another species of saw-fly lives in 

 large numbers on the pine, another on the white birch, 

 another on the rose, another on the currant, and usu- 

 ally there are so many together that a child thinks the 

 group a great treasure, and is disappointed when it is 

 not received with enthusiasm. Some of the saw-fly 

 larvae liave an unpleasant liabit of discharging from 

 glands on their sides a disagreeable, slimy fluid. This 

 is their protection from birds and squirrels. 



Great numbers of " woolly bears " will be brought in 

 late in the season. Those with white, pale yellow, and 

 fox-colored hairs will probably spin in the autumn, but 



