250 B. H. gra^':e 



THE LARVA 



The larva, when full grown, measures between 5 and 8 mm. n 

 length. Seven millimeters may be considered the normal length 

 for the species. It may be supposed that the larvae continue to 

 feed and grow until the supply of food is cut off by the falling 

 of the leaves. They seem to be unharmed by the autumn 

 frosts. 



The color of the larva varies from yellowish or straw to white, 

 except the head, ^vhich is brown. 



The body is flattened (depressed) in the dorsi ventral plane. 

 Twelve thoracic and abdominal segments can be counted. The 

 abdomen ends in a slender tip which may represent an additional 

 segment. The first thoracic segment consists of two annulae. 

 The segmentation throughout is deeply marked and the strong 

 lateral prolongations of the abdominal segments seem to be 

 characteristic. 



Thoracic appendages are wholly undeveloped or do not appear 

 on the surface. 



The antennae are well developed but short, and are directed 

 straight forward. Each consists of four segments, counting a 

 short, thick basal segment. 



The mouth parts are best described in connection with the 

 figures (figs. 5 and 6). They are similar to those of other biting 

 insects except that each part has interesting characteristic fea- 

 tures. The labium consists of the mentum, sub-mentum and 

 gula, but it bears no palpi. The maxillae appear to be immature 

 and the typical parts are not clearly defined in preparations 

 examined. The three-jointed maxillary palpi are well developed. 

 The mandibles have a smooth knife-blade-like cutting edge and 

 are beautifully hinged at two points, one dorsal and the other 

 ventral, as shown in figures 5 and 6. The external and internal 

 mandibular muscles are shown in figure 5. It is to be noted 

 that the muscle fibers are not inserted directly into the mandible 

 but are joined to it by a tendon of connective tissue. The 

 labrum has a scalloped or incised edge and consists of two lobes, 

 as shown in figure 5. 



