OAK-BORERS. 67 



which are several minute maggots or footless little grubs, soft, dull white, shining, of 

 a long egg shaped form, pointed at the tip and blunt in front, their bodies divided into 

 segments by very fine transverse impressed lines or sutures. They are about one- tenth 

 of an inch long and 0.0.35 broad at the widest part. These are evidently the larvae 

 of some small Hymenopterous or bee-like insect, pertaining, there can be little doubt, 

 to the family Chalcididfe, the female of which has the instinct to discover these 

 borers, probably in the earlier periods of their life when they are lying directly be- 

 neath the bark, and piercing through the bark with her ovipositor, and puncturing 

 the skin of the borer, drops her eggs therein, which subsequently hatch and subsist 

 upon the borer, eventually destroying it. These minute larvae were forwarded to me 

 under the supposition that they were injurious to the apple tree, whereas, by destroy- 

 ing these pernicious borers, it is evident they must be regarded as our best friends. 

 This fact illustrates how important it is for us to be acquainted with our insects in 

 the different stages of their lives, that we may be able to discriminate friends from 

 foes, and know which to destroy and which to cherish. (Fitch.) 



Zarva.— Protborax very broad, being broader and flatter and the abdominal seg- 

 ments 81 aller in proportion than any other borer of this family known to us. Head 

 retracted within the prothorax. The disk finely shagreeued with raised dots. A 

 narrow inverted V-shaped smooth impressed line in the middle of the disk, the apex 

 becoming prolonged towards but finally becoming obsolete at the front edge of the 

 disk ; the arms of the V behind not reaching very near the posterior edge of the disk. 

 Beneath, is a similar roughened disk, but more regularly rounded-oval than above, 

 and with a single straight median swollen impressed line, which is a little over 

 one-half as long as the disk, but which reaches a little nearer the front than the hind 

 edge. 



Second thoracic (mesothoracic) segment very short, considerably shorter and wider 

 than the third, with an oval, slightly rough, area on each side of the median line, the 

 similar area on the third thoracic segment being larger and united over the median 

 line. 



The ten abdominal segments of uniform width, being a little shorter than broad, 

 except the small tenth segment, which is about two-thirds as wide as the ninth. A 

 pair of irregular, rather long patches on each abdominal segment above, and a pair 

 of curvilinear impressed lines beneath. 

 One pair of mesothoracic and eight pairs of abdominal spiracles. 

 Head a little narrower than the thoracic disk. Clypeus corneous, square in front- 

 very short and broad. Labrum square, a little longer than wide, front edge mode, 

 rately rounded, densely hirsute. Antennae 3-jointed; first joint short, membranous, 

 second considerably narrower, third minute, rounded at tip, considerably slenderer 

 than second. Mandibles entirely black. Maxillary lobe short, projecting slightly be- 

 yond the edge of labium. Maxillary palpus 2-jointed, second joint not so long as the 

 first is wide, one-third as thick, and extending a little beyond the maxillary lobe. 

 Labium entire, the front edge not being excavated. 



Length, 22"'"> ; breadth of prothoracic segment, 7"""' ; length, 4""" ; width of sixth 

 abdominal segment, S"""". 



Pupa. Body flattened, and of the general shape of the imago. The antennae seen 

 from above extend to a little behind the outer hinder angle of the prothorax. The 

 elytra reach to the middle of the fourth abdominal segment. The wings extend as far 

 as the hinder edge of the same segment. The third pair of tarsi reach to near the 

 middle of the sixth abdominal segment. Six pairs of abdominal spiracles. Length, 

 15°"" ; breadth, 7""^. 



In transforming, the eyes, the front of the head, the prothorax, the femora, and 

 tibiae and portions of the sternum and under side of the abdominal segments turn 

 dark first. 



The foregoing descriptions have been drawn up from specimens ob- 

 tained by us in Texas and in Rhode Island. 



