FAMILY SERICOSTOMATID^ 



The caddis flies of this group are usually excessively hairy. 

 They vary much in form. Their larvae usually inhabit streams 

 and not ponds, and the flies are generally found near the 

 breeding places. The larval cases are usually of the ordinary 

 cylindrical form. They are free, and generally made of sand or 

 small stones, but sometimes the cases are broad and flattened 

 and sometimes they are quadrangular, and the most remark- 

 able of all are those which are constructed in the shape of a 

 snail-shell. An almost perfect helix is made by some of them, 

 and it is one of these which, as mentioned above, was described 

 by a conchologist as a new species of snail. That was at a time 

 when shell students described the shells and cared nothing for 

 the animal which inhabits them. We have in the United States 

 a number of species in this family, separated into nine genera, 

 most of the forms being northern, although the two typical 

 Sericostomas inhabit Georgia. 



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