U8 Bulletin No. 159 



creeping about as if free. Several species were collected in 

 the waters examined, together with others which construct 

 and drag about with them very characteristic cases. Some 

 of these cases obtained are composed of bits of sand glued 

 together in a spiral form so as to resemble a small snail 

 shell, the larva living within, keeping its head and rather 

 long legs in the opening. Other cases collected are cylin- 

 drical and composed of bits of wood or other vegetable 

 matter. Types of the different larvae and of the cases are 

 described and figured so as to give a definite idea of their 

 appearance. These singular and interesting larvae are in 

 part'predatory and carnivorous, such members of the group 

 frequenting the situations preferred by Simulium larvae, 

 and probably at times act as enemies or competitors of the 

 latter; in fact Miall definitely states it to be a fact that 

 European species feed upon Simulium. 



When ready to become pupae case-fly larvae secure their 

 cases to rocks or other heavy objects in the water, close up 

 the apertures, leaving, however, openings for the circulation 

 of the water, and become quiescent. A single pupa, prob- 

 ably one of the net-making species, was taken from Straight 

 Creek near Pineville, enclosed in a short case made of coarse 

 bits of sand, the whole attached to a rock. Adult case-flies 

 are delicate little four-winged insects often seen at lights in 

 dwellings, and in very large numbers about the arc electric 

 lights of towns and cities in the State. They look somewhat 

 like a clothes moth, and are not commonly discriminated 

 from these insects, all being called candle flies. A species 

 (Hy dropsy che speciosa) with blotched wings is especially 

 common at times in midsummer about the electric lights at 

 Lexington. They are all harmless to us. 



Case-fly No. l.—A cylindrical case, with small bits of 

 woody material fastened over the surface. Straight, or a 

 little curved, the smaller extremity fitted with a round disc 

 within the aperture, provided with a single slit-like opening. 

 About this end, some bits of sand are attached as if to 

 anchor it. Length 13 mm.; diameter 2.5 mm.; at smaller 

 end, 1.8 mm. Another example measures 14x2.9x2.6 mm. 



