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MEMOIKS OF THE NATIONAL ACADEMY OF SCIENCES. 



Suborder I. — Lepidoptera laciniata on Peotolepidoptera. 



The taxononiic importance of Walter's most iDterestiiiy discovery, that Eriocepliala calthella 

 lias inaxilhe coustructed ou tbe type of those of biting or mandibulate insects, i. e., with an inner 

 (galea) and outer lobe (laciiiia) besides the palpi (tig. 2), was apparently overlooked by him as 

 well as others, though its bearings on the phylogeuy of the Lepidoptera, insisted on by Walter, are. 

 it seems to us, of the highest interest. The i)resence of two maxillary lobes, homologous with the 

 galea and lacinia of the Mecoptera (Pauorpidie) and Neuioptera (Corydalus, Mymeleou, as well 

 as the lower orders, Dermaptera, Orthoptera, Coleoptera, etc.) in what in other important respects 

 also is the ''lowest" or most primitive genus of Lepidoptera, the lacinia being a rudiniental, 

 scaroelj' functional, haustellum or tongue, and not merely a vestigial structure, is of great 

 significance from a phylogenetie point of view, besides affording a basis for a 

 division of the Lepidoptera into two grand divisions or suborders, for which 

 we would propose the names Lepidoptera laciniafa and Lepidopteta haiisicUata. 

 Walter thus writes of the first pair of maxilhe: 



The other mouth parts also of the lower Micropterj-giuii' have a most iirimitivo char- 

 acteristii-. In tbo first pair of maxilla' of Micropteiyx caltheUa, uruncella, atulenschdUi. aud 

 anreatdla, eardo and stipes are present as two clearly sejiarate pieces. The former iu J/. 

 caltheUa and arunceUa, in comparison with the latter, is larger than in midiirselu-Ua and 

 uiireatella. Iu the List two species the cardo is still tolerably broad, but reduced. The stipes 

 is considerably longer than the cardo iu the last two species, while it is of the same thickness. 

 From the stipes arises the large sis-jointed palpus maxillaris, making two or three bends 

 and concealing the entire front of the head and all the mouth parts. At its base, and this 

 is unique among all tbe Lepidoptera, two entirely sejiarate maxillary lobes arise from the 

 stipes. The external represents the most primitive rudiment' (anlage) of a lepidopterous 

 tongue. (Fig. 2.) 



It is evident from Walter's figures and description that this strncture is not 

 a case of reduction by disuse, but that it represents the primitive condition of 

 this lobe, the galea of the maxilla, and this is confirmed hy the presence of the 

 lacinia, a lobe of the maxilla not known to exist iu any other adult lepidopterous 

 insect, it being the two gale* which become elongated, united, and highly 

 specialized to form the so-called tongue, haustellum, or glossa of all Lepidojjtera 

 above the Eriocephalidte, which we may therefore regard as the types of the 

 Lepidoptera laciniatap- 



Another most imjiortant feature correlated with this, and not known to exist 

 in Lepidoptera hausteUaia, is the presence of two lobes of the second maxilhe, besides the three- 

 jointed labial palpi, and which correspond to the mala, exterior and mala interior of the second 

 niaxilltB of Dermaptera, Orthoptera, Platyptera, Perlid;e, Termitidie, and Odonata, and also, as 

 Walter states, to the ligula and i>aragloss;t of Ilymenoptera. In this respect the laciniate 

 Lepidoptera are more generalized insects than the Tricboptera or Mecoptera. 



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



Within and at the base of the labial palpi is a pair of chitinous leaves provided with stiff bristles, being the 

 external second lobes of theunderlip, formed by the consolidation of the second pair of maxilla- and which reach when 

 ■extended to about the second third of the length of the second jialpal joint. Its inner edge is directly connected with 

 the inner lobe (mala interna). The latter are coalesced into a short wide tube which, by thegi'eater size, of the hinder 

 wall, opens externally on the poiut, also appearing as if at the same time cut otf obliquely from within outward. 



■In accordance with an English author, I think, but whose name escapes me, I use the term rudiment in the 

 «ense of the German word Aulage, and vestige for an organ which has or is undergoing reduction, degeneration, or 

 atrojjhy. I am aware that the word Aulage has no English equivalent, but can scarcely accept the word 

 "fundament" as better than rudiment. We may, then, speak of germs or rudiments, and of rudimentary when 

 referring to the incipient organs of the young or adult, regarding vestigi.al organs as those on the point of atrophy 

 from disuse. The term blast for Aulage I should accept for emliryonic structures iu their incipient or germinal 

 •condition. 



- In his paper on the larva of Eriocephala, etc. (Trans. Ent. Soc. London, 1894, p. 335), Dr. Chapman separates 

 the old genus Micropteryx into two families: Eriocephalida' .and Microptcrnyidw. His groui> Eriocephalida' I Iiave 

 regarded as comprising the type of the suborder Lepidoptera hiciniata or Protulepidoptera. 



Fig. 2.— Maxilla of 

 Eriocephala caltheUa ; 

 2. lacinia; g, galea; 

 inx.p, maxillary pal- 

 pus; St, stipes; c, 

 -cardo. — After Walter. 



