LEPIDOPTERA 611 



several families of small moths, hence this name is no longer distinc- 

 tive. Among the families of small moths removed from theMicro- 

 lepidoptera are theMicropterygidae and theEriocraniidae, now placed 

 in the suborder Jugatee; the Incurvariidas and the Nepticuli das, placed 

 at the beginning of the Frenatse; and the group of families now known 

 as the Pyralids, which are believed to be genetically quite distinct 

 from the other families of small moths. On the other hand, in ad- 

 dition to the families here placed in this series some authors include 

 the Cossidae. 



The families of the Microfrenatas are grouped into superfamilies 

 in various ways by different writers ; but none of these groupings is 

 sufficiently well established to be adopted here. 



Family ACROLOPHID.E 



These are large, stout, noctuid-like moths; some of the species 

 have a wing-expanse of 30 mm. or more. The eyes are usually hairy, 

 in which respect they differ from other "Micros." The antennas are 

 without an eye-cap. The labial palpi are large, and usually upcurved 

 to the middle of the front; in the males of some species they are 

 thrown back on the dorsum of the thorax, which they equal in length. 

 The first segment is relatively very large; when the palpus is short 

 it is longer than the second segment ; the thorax is tufted. The vena- 

 tion of the wings is quite generalized ; the base of media is more or 

 less preserved, and all the branches of the branched veins are present ; 

 there are three anal veins in both fore and hind wings; in the fore 

 wings the tip of the third anal vein coalesces with the second anal 

 vein. 



Fort\^-two species have been described from our fauna; these 

 were formerly classed in several genera ; but recent writers refer them 

 all to the genus Acrolophus. 



The burrowing web-worms, A. arcanellus, A. mortipennellus , and 

 A. popeanellus. — The habits of these three species were described 

 by Professor Forbes in his Twelfth Illinois Report (1905). The larvae 

 normally live in the ground feeding on the roots of grass. Each larva 

 makes "a tubular web opening at the surface and leading down into 

 a vertical cylindrical burrow about the diameter of a lead-pencil, and 

 six inches to two feet, or even more in depth." The larva measures 

 about 25 mm in length. Sometimes the larvae injure young com 

 when planted on sod. They surround the base of each plant with a 

 fine web mLxed with earth and pellets, building this up in the lower 

 blades, which they slowly eat away. As they get larger they eat the 

 stripped plant to the ground. When disturbed they retreat into 

 their web-lined burrows. 



Family TINEID^ 



The head is usually clothed with erect hair-like scales. The 

 antennae are shorter than the front wings. The maxillas are usually 

 small or vestigial. The maxillar>^ palpi are usually large and folded. 



