158 PKOCEEDINGS ENTOMOLOGICAL SOCIETY 



with several, the pupa has a period of rest after emergence from 

 the cocoon, during which the mandibles and the head work fu- 

 riously at the least irritation with a hair-pencil, or even without 

 such. This period evidently corresponds to the time it normally 

 takes the pupa to work its way through the soil to the surface. 

 Later on comes the period of immovability of the mandibles, 

 which fail to respond even if sharply irritated. This corresponds 

 to the resting period when the pupa under normal conditions has 

 reached the surface. 



The imago has the head (fig. 22) and face strongly tufted with 

 long gray, brown and white hairs, which obscure the eyes and 

 mouthparts. The antenna? are simple, dark brown, with two 

 longitudinal light yellow lines throughout their length. Thorax 

 strongly haired, the long brown and gray hairs arranged in three 

 large whorled tufts, two over the patagia and one posteriorly. 

 Fore wings elongate elliptical, thickly covered with large golden 

 scales, evenly interspersed with numerous single purplish blue 

 metallic scales: cilia light golden brown Hind wing dark golden 

 brown, with a purple sheen, semitransparent at base; cilia gray. 

 Abdomen brownish gray, in the female terminating in a short, 

 stout, brown, horny ovipositor. Legs dark gray sprinkled with 

 purple scales; posterior tibiae with long, sparse thin hairs on the 

 upper side and with two pairs of well developed spurs. Alar 

 expanse 10-13 mm. The venation is given in figures 12-13. 



From the several clearly primitive characters which they pos- 

 sess in common, more especially in the neuration and the mode 

 of keeping the wings together by the so-called jugum (the clavus 

 of Spuler), there can be no doubt that the Eriocranidve and the 

 Micropterygidse represent the most ancestral group of Lepidop- 

 tera. This has been generally recognized by all modern Lepidop- 

 terists, but there has been considerable difference of opinion as to 

 the relative systematic value of these groups. Some authors have 

 considered the active biting mouth parts of the adult Microp- 

 terygidaB of sufficient systematic value to separate this group as a 

 distinct superfamily or even subclass. On the other hand, Mey- 

 rick regards the passage to sucking mouth parts in the Eriocrani- 

 da3 as a purely biological change of structure of much less system- 

 atic significance, and he treats the two groups as closely allied 

 subfamilies. 



The actual presence of rudimentary but unmistakable mandi- 

 bles also in the Eriocranidse tends to support Meyrick's opinion of 

 close correlation, but his. description (Genera Insectorum), con- 

 tains some misstatements and omissions in the anatomy of the 

 head structures in the two groups. We consider that the differ- 

 ences both in the mouth parts and in the venation, as well as of 



