252 HALF HOURS WITH INSECTS. [Packard. 



in these small neglected forms do we want a large number 

 of observers. It would be an admirable subject of study for 

 ladies, as the leaves containing them can be easily gathered, 

 and if laid on wet sand in airy boxes or jars, the moths can 

 be bred with much less trouble than the larger species.* 



The walnut and hickory entertain a larger host of insect 

 pests than any other deciduous tree ; some seventy species 

 are already known to draw their supply of food from these 

 noble trees. Our black walnut wood comes from the western 

 states, particularly Indiana, where the tree grows in the 

 greatest perfection. It is estimated that within so short a 

 period as ten years from the present date, the supply of 

 black walnut lumber will be materially diminished. It is 

 even now time to be planting groves of these precious trees 

 in the western states. "When they are in course of cultiva- 

 tion we can, in the imagination, if a scientist may be allowed 

 to use that potent weapon, see the entomological evils which 

 will cluster about those groves : a hundred different sorts 

 of insects, represented by thousands of individuals, laboring 

 away at root, branch, leaf, bud and fruit, unwittingly de- 

 stroying the sapling, while securing their own means of 

 livelihood. 



Not to bore the reader with dry accounts of the beetles 

 which occur in the walnut, we would allude to the tigrine 

 Goes, which does the most serious damage to the trunks, as 

 it bores large holes in the solid wood, lengthwise to the 

 tree. The grub is rather large, cream-colored, with the head 

 and the segment next to it yellowish. The beetle is a longi- 

 corn — we are now pretty familiar with the appearance of 

 these longicorns with their remaj-kably long antennae — and 

 is brown, covered with a dense tawny pubescence, with a 

 broad dark band beyond the middle of the wing covers, and 



*Full directions for rearing caterpillars may be fonud in "Directions for 

 collecting and preserving Insects," prepared for the use of the Smithsonian 

 Institution by tlie writer. 



28 



