ANNETTE F. BHAUN. 273 



GROUP I. 



The larva of the first (iroup (Plate XX, fig. 11) i^; cylindrical or 

 subcylindrical in form, and has, beside the thoracic legs, four pair 

 of prolegs, on 7, 8, 9 and 13. It is usually of a pale greenish or 

 yellowish color. 



The mine may he placed upon either the upper or lower surface, 

 hut in either case the loosened epidermis is lined with silk, causing 

 it to contract, thus producing a roomy, tent-like mine. The mine 

 is at first narrow, somewhat winding, but soon spreads out into a 

 blotch, which sometimes includes the earlier winding portion. The 

 outline of the loosened epidermis represents the final size of the 

 mine, no further increase taking place. The mine may be oval or 

 circular, or in a few cases, nearly rectangular in shape, sometimes 

 limited by two veins. Usually the larva feeds from the circumfer- 

 ence inwardly; sometimes it begins at one end, and sometimes it 

 feeds irregularly in spots. 



With the exception of odensackenella, which leaves the mine to 

 pupate, the pupa is formed within the mine, and may or may not be 

 enclosed in a cocoon. In the latter case, it is usually suspended in 

 the mine by a thin meshwork of silken threads. Where a cocoon 

 is present, sevei'al varieties may be distinguished. It may be I'ather 

 small, ovoid, formed of frass and silk ; large, loosely woven, semi- 

 transparent, occupying sometimes nearly one-half the mine; or an 

 oval ring with outlines formed of frass. 



The forewings of the imagoes are usually of some shade of vellow 

 or brown, sometimes, however, with the basal two-thirds almost 

 pure shining white. Upon this yellowish ground color, the more or 

 less white markings appear. The transverse n)ai'kings consi.-it of 

 costal and dorsal streaks, usually curved and oblique, slightly curvetl 

 or anguhited fascise or combinations of these. These streaks or 

 fascite are usually margined with darker scales toward the base; the 

 internal margins of some of the streaks are sometimes lacking. In 

 a few species some or all of the streaks or fasciae may be more or 

 less margined externally also, but in no case is the external margin 

 heavier than the internal one, and in no case is an external margin 

 present, when the internal one is absent. Longitudinal markings, 

 when present, consist of a nunlian streak from the base, sometimes 

 accompanied by streaks along the costal and dorsal margins. The 



TRANS. AM. ENT. SOC. XXXIV. (35) SEPTEMBER. 1908. 



