231 



states, in the form of true gnawing jaws, like those of the biting in- 

 sects. They possess powerful chitinous teeth on the opposed cutting 

 edge, 12 to 15 on each mandible, and also the typical articulating 

 hook-like processes by which they are jointed to the genae, and fit in 

 corresponding cavities in the latter. In Micropterrjx and other of the 

 more generalized moths the mandibles in a very reduced form have 

 survived as functionless vestiges of the condition in Eriocephala. 



Turning now to the head and trunk, we find other primitive cha- 

 racters correlated with those just mentioned. 



The head is of moderate size , as well as the body, with small 

 compound eyes, and with two ocelli. The occipital region is Avell de- 

 veloped , as is the epicranium ; the clypeus and labrum are of mode- 

 rate size. 



The generalized nature of the thorax is especially noteworthy. 

 The prothorax is very much reduced , the two tergites being separate 

 and minute, not readily seen from above. The rest of the thorax is 

 very long, exhibiting but little concentration. 



The mesothorax is but slightly larger than the metathorax , the 

 mesoscutum is very short , the scutellum rather triangular than scu- 

 tellate. 



The metathorax is but little shorter and smaller than the meso- 

 thorax and remarkable for the widely separated halves of the scutum, 

 a Neuropterous character (compare Ascalaphus and Corydalus)^ in 

 which it differs from Microptei'yx. The shape of the scutellum is that 

 of a low flattened triangle. 



As regards the abdomen, attention should be called to the dispar- 

 ity in size and shape between the sexes , also to the male genital ar- 

 mature which is very large and completely exserted , and reminds us 

 of that of Corydalus , in which however the lateral claspers are much 

 reduced, and also of that of certain Trichoptera {Sericostoma, Tinodes, 

 Stenophylax, Hydropsyche^ etc.). 



The larval characters of this suborder it would be difficult to give, 

 for in the remarkable larva of Eriocephala calthella as described and 

 figured in Dr. Chapman's elaborate account 3, we appear to have 

 a highly modified form, entirely unlike the simple apodous larva of 

 Micropteryx and perhaps quite unlike the primitive stem-forms of 

 lepidopterous larvae. Chapman's well represented its form, as we 

 can testify from mounted specimens in a slide kindly given us by 

 him. The body is broad and flattened, the segments very short in 

 proportion to their width , the prothoracic segment , however , very 



3 Trans. Ent. Soc. London, 1894, p. 335. I am indebted to Dr. Chapman for 

 mounted specimens of the larvae, and for examples of the imago. 



