THE MICROPTERYGIDES. 131 



So marvellous were the facts brought** to our notice by Chapman, and 

 so far-reaching were the suggestions made as to the relationships of the 

 insects, that it seems difficult even now for us to recognise that insects so 

 different in size, shape, and general appearance, should be related, to the 

 exclusion of others, to families with which one could not suppose they 

 bore any relationship. The presence of characters common to the Microp- 

 terygids, Eucleids and Anthrocerids, and absent (so far as is known) 

 in all other Lepidoptera, bespeaks an affinity, in spite of the number- 

 less links that have been extinguished in the course of their evolution. 



The Micropterygides, then, form a superfamily containing some of 

 the most ancestral of all Lepidoptera. The species have no near 

 relatives, although the Eriocraniides and Hepialides have been 

 united with them, but the alliance has little more in it than the fact 

 that these three superfamilies are amongst the, if not the, most 

 ancestral of all Lepidoptera, and have had no real connection since a 

 geological time which is almost inconceivable. Through all these ages 

 they have retained certain ancestral characters, and whilst thousands 

 of other forms have come, given rise to new forms, and then dis- 

 appeared, leaving us only here and there a group that has been able to 

 withstand the climatic and other changes of so vast a geological period, 

 these have gone on, modified, of course, to a great extent, but retaining 

 many of the features that distinguished them, probably as far back as 

 the Carboniferous or Silurian periods. It is possibly this cause that has 

 made the vast gap between the generalised and specialised families of 

 each stirps, for there can be no doubt that many of the latter {e.g., the 

 Geometrids, Noctuids, etc.), have been evolved in recent times, 

 probably in the Tertiary, certainly one would suppose not before the 

 Cretaceous, period. When, therefore, one wonders at the inclusion 

 of the Micropterygides in a stirps of which the highest superfamilies are 

 the Saturniids and the Sphingids, it must not be forgotten that the 

 former are just a little branch of a stem that has divided endlessly, 

 and given rise to a multiplicity of forms under an almost inconceivable 

 variety of conditions, whilst all this time this little superfamily itself 

 has been the sport of the same varying conditions, and yet has retained 

 those characters which enable us to judge of its antiquity. 



It is not easy at once to uproot one's cherished associations so as 

 to separate the Micropterygids (Eriocephalids) from the Eriocraniids, 

 with which superficially they appear to have so much in common, 

 especially in size, colour, and neuration ; but Chapman's comparison 

 of the two superfamilies (Trans. Ent. Soc. LoncL, 1894, p. 336), shows 

 us that Meyrick's attempt (Handbook, etc., pp. 802-805) to keep them 

 as genera of the same family is not at all in accordance with the facts 

 at our disposal. There seems, therefore, not only a necessity to place 

 them in different superfamilies, but practically on different stirpes in 

 the classification we have adopted in this work. So far as we at pre- 

 sent know, the Palrearctic species belonging to the superfamily 

 Micropterygides are not only referable to the same family, but also 

 to the same genus Micropteryx, Hb. ( = Eriocephala, Curt.) . The charac- 

 ters of the genus Micropteryx are given f by Chapman as follows : — 



* " Micro-Lepidoptera whose larvse are external feeders," Trans. Ent. Soc. 

 Lond., 1894, pp. 335 et seq. 



t " Some notes on Micro-Lepidoptera," etc., Trans. Ent. Soc. Lond., 1894, 

 p. 336. Revised in litt., May 5th, 1898. 



