34 



may at least approximate this in reference to the borers, and ascer- 

 tain the group to which the respective larvae belong, and thu's gain 

 a pretty correct idea of their habits in the other stages of their lives. 



As the first step in grouping them by their larval or worm charac- 

 ters, we may separate them into two divisions, thus : 1. Those pos- 

 sessing feet; 2. Those which are footless grubs. 



The first division maybe again divided into sections, thus : 1. 

 Those having but six feet or legs, which are true legs, terminating in 

 a claw, and are situated on the three front segments, immediately be- 

 hind the head. 2. Those having not only the six true legs, but also 

 ten or twelve thick, flehv, short legs situated on the middle and hind 

 segments. 1 presume it is well known to all of my readers that larvae 

 often possess two kinds of legs : first, the true legs, of which, when 

 any are present, there are six, always situated on the first three seg- 

 ments behind the head, and are jointed and terminate with a claw. 

 These are called "true," or "thoracic," legs. The others are thick, 

 Heshy, unjointed, and usually very short legs, situated on some of the 

 remaining segments. These are called "prolegs," or "abdominal" legs. 



Borers which have any prolegs, generally, and so far as Illinois is 

 concerned we may say always, have ten of these, which, with six true 

 legs, gives them sixteen. The prolegs are placed, one pair on each, 

 the sixth, seventh, eighth and ninth segments, and one pair on the 

 last segment. These are true caterpillars, and all belong to the order 

 Lepidoptera, and in the perfect .state are moths. They belong to the 

 two families, or rather sub-families, Cossidae and Aegeriadae. 



These groups may be distinguished, so far as our insects are con- 

 cerned, by their operations, as well as by the characters of the larvae 

 themselves. The former, Cossidae, or, as Harris and some other ento- 

 mologists name the group, Hepialidae, are trunk-borers; the Aegeriadae 

 operate in the roots of trees, stems, and canes of shrubs, or under the 

 bark of the trunks of trees, seldom penetrating into the wood. Our 

 only troublesome species belonging to Cossidae, or locust borer 

 i Xyleutes robinia ), when fully grown in the larval state is nearly three 

 inches long. The larvae of this group, or rather of this genus,' which 

 is limited to the carpenter moths, are white, or reddish white, soft 

 and naked, or nearly so, with brown heads, and a spot on the front 

 part of the body alone, which is brown and hard; they are elongate 

 and comparatively slender, cylindrical, and have the indentations 

 between the segments deep. 



The Larvae of the Aegeriadae are whitish, soft, and slightly down}-, 

 and small ; usually somewhat flattened beneath, and the segments not 

 usually bo deeply divided. The peach root borer (Aegeria exitiosa) is a 



familiar example of this family. 



We see. therefore, that we need to look to bul two families of moths 

 for our borers which have more than six legs. 



Those larva which have but six true legs may be divided into two 

 groups, thus: Those which have a horn or spine projecting from the 

 tails, and those which have not., 



The former of these two groups are cylindrical, Heshy grubs, of a 

 whitish color, with a small, rounded, horny head and a pointed, horny 

 tail, with six smalllegs under the front partofthe body. They gener- 

 ally attack pines and firs; but the pigeon tremex (Tremex cMumba), 



