19 lo] A Structural Study of Some Caterpillars 115 



2. Labruni cleft about a third its height; setae ii only moderately 

 out of line with i; body with tufts i and u of four abdominal segments 

 fused into large square masses. 



Example Hemerocampa leucostigma. Fig. 98. 



1. Labrum less deeply notched, vi nearly marginal; adfrontals 

 slender, their secondary setas inconspicuous; front with secondaries, 

 especially in the lower part ; epicrania with a good deal of hair above 

 setae ii- warts i and ii of the first abdominal segments fused to each 

 other, but not fused across the median line. 



Example Euproctis chrysorrhea. Fig. 99. 



NOCTUIDAE. 



Prolegs with hooks in a single band, not alternately of two lengths. 

 Usually without secondary or tufted hair, but both are present on the 

 body in Pantheinae and Acronyctini; head with secondar)."- hair on 

 the epicrania, maxillae and labium in the Pantheinae only. Front large, 

 more than a third of the height of the head above the clypeus, the 

 frontal punctures usually close together, never nearer to the setae 

 than to each other ; labrum with puncture ia considerably nearer to i 

 then to ii, not very high up ; ad frontal puncture rarely more than twice 

 as close to upper as to lower seta ; maxillae and labium of about equal 

 width ; the submentum at least as wide as the base of the mentum, the 

 labial setae ai close together. Setae of abdomen all well separated, 

 / somewhat higher than ii, iv higher than v, vi always single and vii 

 with three setae except in forms with tufted hair; no caudal horn. In 

 those with tufted hair there are four warts on thorax above the legs, 

 on abdomen three above and two below the spiracle, besides vii and 

 viii. Never with eversible dorsal glands; anal legs with more hooks 

 than ventrals, one or two pairs of ventral legs often reduced or absent, 

 but never three. 



Pantheinae: Epicrania, maxillae and labium with considerable 

 secondary hair; adfrontals wide above the top of the front, the punc- 

 ture about half way between the setae, and above the top of the front. 

 Body with tufts and pencils, with secondary hair also,, in Panthea. 

 Example Demas coryli. Figs. 100 and 101. 



NocTUiNAE : Head without secondary hair, body occasionally with 

 tufted and secondary hair, or tufted hair only. Adfrontal puncture 

 below the top of the front, and adfrontals rarely much widened at the 

 top (Apatela interrupta ) ; anal legs directed downwards and not length- 

 ened; setae usually short except in hairy forms, distance between upper 

 adfrontal setae less than half height of front ; distance between 

 frontal punctures not less than a third that between seta and puncture. 



In this group of Noctuinae (or Trifidae) there is a good deal of 

 minor variation between different genera, and even species of the 

 same genus, but my series of forms, though larger than of any other 

 family so poorly represents this enormous group that I shall only 

 characterize the two tribes Acronyctini and Cuculliini (Cucullianae of 

 Hampson) and mention a few peculiarities of some other genera.* 



* I have done nothinpr whatever with the body setae. Dyar discusses seta iv in Proc. Ent. Soc. 

 Wash. IV, 370 and Pird, in Can. Ent. Vols. 32-34, 39, 40 refers oi^en to variations in the tubercle 

 of the gen.us Pap'aipema. See also m>' 'Field Tables." patre 140. 



