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correspond to the mala exterior and mala interior of the second 

 maxillae of Dermaptera , Orthoptera, Platyptera, Perlidae, Termitidae 

 and Odonata, and also, as Walter states, to the ligula and paraglossae 

 of Hymenoptera. In this respect the laciniate Lepidoptera are more 

 generalized insects than the Trichoptera or Mecoptera. 



Walter thus describes the two lobes or outer and inner mala of 

 the second maxillae : »Within and at the base of the labial palpi is a 

 pair of chitinous leaves provided with stiff bristles, being the exter- 

 nal lobes of the un der lip formed by the cosolidationofthe 

 second pair of maxillae, and which reach when extended to about 

 the second third of the length of the second palpal joint. Its inner 

 edge is directly connected with the inner lobe (Mala interna). The 

 latter are coalasced into a short wide tube which by the greater size 

 of the hinder wall opens externally on the point, also appearing as if 

 at the same time cut oif obliquely from within outwards.« 



»The outer exterior edge of the tube forms a strongly chitinous 

 semicircle which becoming thinner finally passes into the delicate 

 membranous hinder wall. Also anteriorly a delicate membrane appears 

 to cover the chitinous portion.« 



»We have here in opposition to the weak naked under lip repre- 

 sented by a triangular chitinous plate in other Lepidoptera , a true 

 ligula formed by the coalescence of the inner lobes of the second max- 

 illae into a tube, as in many Hymenoptera, and with free external 

 lobes, which correspond to the paraglossae of Hymenoptera.« 



Walter has also detected a paired structure which he regards as 

 the hypopharynx as he states : » A portion of the inner surface of the 

 tube-like ligula is covered by a furrow- like band which close to the 

 inner side is coalesced with it, and in position, shape, as well as its 

 appendages or teeth on the edge may be regarded as nothing else than 

 the hypopharynx.« While he refers to Burgess' discovery of a hypo- 

 pharynx in Daiiais archippus, he remarks that this organ in the lower 

 Micropteryginae [Eriocephalidae) exhibits a great similarity to the re- 

 lations observable in the lower insects, adding: »The furrow is here 

 within coalesced with the inner side of the labium, and though I see 

 in the entire structure of the head the inner edge of the ligula-tube 

 extended under the epipharynx as far as the mandible I must also 

 accept the fact that here also the hypopharynx extends to the mouth- 

 opening, as in all other sucking insects with a well developed under 

 lip, viz., the Diptera and Hymenoptera.« 



Another feature of importance diagnostic of this suborder , is the 

 mandibles, which in form, size and the presence of teeth are closely 

 related to those of the lower mandibulate orders, being, as Walter 



