NORTH AMERICAN CADDIS-FLY LARVE. 
Each of these segments bears an indistinct pattern of pale, narrow 
marks on its soft dorsal surface. 
Abdomen.—The abdomen is without external gills. The pro- 
legs are turned at right angles to the axis of the body, and bear 
drag-hooks of extremely small size, which are apparently put to 
but little use. 
Description oF CasE.—The case of the larva, figures 196, 197, 
is made of small pebbles or large sand grains. In form it appears 
much like a diminutive turtle. On the lower side, figure 197, there 
is a floor of sand grains built across the middle of the case, leaving 
the two ends open on the bottom, but completely covered on the 
upper surface. This case is freely movable over the surface of 
rocks. 
The case of the pupa differs from the case of the larva only in 
having no floor. The rim of the case is tightly cemented to some 
submerged rock, and inside of the inverted cup thus formed the 
cocoon is spun and pupation takes place. 
GENUS AGAPETUS. 
An unreared species of the subfamily Glossosomatine, which 
agrees well with published European descriptions of the genus 
Agapetus, was collected in Michigan Stream above Spencer Lake. 
The larve differ from the larve of the genus Glossosoma in 
having a pair of large chitinous shields on the mesothorax and a 
pair of smaller shields on the metathorax. The prolegs and drag- 
hooks are larger than those of Glossosoma. 
The cases are similar to those made by Glossosoma, but larger 
pieces of gravel are used in their construction. 
FAMILY HYDROPTILID:. 
This family contains the most minute members of the order 
Trichoptera. For this reason, no doubt, it is the most neglected 
family in the order. Scarcely the first step has been taken toward 
a knowledge of the immature stages in America, and even the 
adults are most imperfectly known. In the present stage of our 
knowledge no attempt at classification is possible. 
The tiny larve inhabit standing or flowing waters, and often 
occur in very great numbers. Often their cases completely cover 
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