372 BRITISH LEPIDOPTERA. 



localities is almost incredible. Chapman states that Constant informed 

 him that Apterona helix, was in thousands on the shore at the mouth 

 of the Var, and that he himself saw certain tree-trunks, at the end of 

 March, 1899, in the Albenga valley, covered with them, they were 

 literally in thousands. These were of course empty cases, all firmly 

 attached to the trees, and were probably an accumulation of several 

 years. According to Ingenitzky (Zool. Anz., xx., p. 473) Psyche helix 

 is found in great numbers near Lake Issyk-kul in Central Asia, where 

 the larvae feed in their snailshell-like cases, on a grass, just like 

 snails. 



How far altitude governs emergence is well exhibited by observa- 

 tions on Standfussia zermattensis. On April 5th, 1899, Chapman found 

 the cases abundant on the rocks, near Ancona, on the shores of Lake 

 Maggiore whilst the male moths were observed on the wing on April 

 15th, but the empty pupa-cases found earlier showed that the species 

 had been out for some time before this. It was still out on June 30th, 

 at 1400ft. elevation, near Bignasco, and one was captured as late as 

 August 5th at Simplon, at 4900ft. These dates all refer to the same 

 season, 1899. 



Petersen notes that the male of 8. siandfussi is reported to fly at 

 night, and states that other Psychids have the habit, as he himself had 

 taken Amicta febretta, in Persia, in the evening at light. 



Our ignorance of the structural details of the higher Psychids, i.e., 

 the Psychidae, is so profound that it is practically impossible to check 

 any system of classification suggested by a consideration of the 

 imagines by reference to the oval, larval, or pupal stages, and even the 

 ? s of most of the species, except as cabinet mummies, are almost 

 equally unknown. It is evident, therefore, that, in any consideration 

 of the relationship existing between the various sections into which 

 this family falls, we have less ground for safe generalisation than in 

 the preceding portion of our work in the superfamily. 



Study of the imagines, however, shows that the $ of the primitive 

 Psychid, by the time that it had evolved sufficiently to be considered 

 as belonging to the Psychidae, had antennae scaled to the ends of the 

 pectinations, an anterior tibial spur of considerable length (-80--85), and 

 a well-developed cellula intrusa, but had almost lost the posterior tibial 

 spurs. It then appears to have divided into two branches : 



1. Preserving the tibial spurs, but with a tendency to lose the antennal scaling, 



2. Preserving the antennal scaling, but losing the tibial spurs. 



In 1, the cellula intrusa was not frequently lost, in 2 it was usually 

 lost. In a branch of 1 (Oiketicids) there appeared a strong tendency 

 to a diminished size of the hindwings, and to a strengthening of the 

 opposed (inner) wing-margin with accessory or newly-developed 

 nervures. The other branch of 1 (Acanthopsychids) had tendencies 

 more like those characterising section 2. 



We have altogether insufficient material to form any valuable 

 conclusion as to the Apteronids. They are clearly a branch of 2 that 

 has developed the scaling of the antennal pectinations into very dense 

 and thick masses of hair-scales. It is very possibly, however, fully 

 entitled to subfamily rank with Acantliopsychinae and Psychinae. 



The Oiketicids (Oiketicus, L.-G., and Lansdownia, Heyl.) and 

 Psychids {Animula, H.-S., Acantlwpsyche, Heyl., Psyche, Schrk., 

 Apterona, Mill.) are defined by Heylaerts as follows : 



