144 TRICHOPTERA. 



arrange transversely, but they by no means confine them- 

 selves to this rule, as sometimes the cases are wholly com- 

 posed of fresh-water shells, often containing their living 

 inhabitants ; sometimes of small stones, and often of all of 

 these substances intermingled. L. peliucidus uses large 

 pieces of reeds and leaves, which it arranges longitudinally. 

 i. vitratus makes a cylinder of sand, or very small stones, 

 but to this it attaches longitudinally large pieces of stick, 

 fragments of wood, straws, &c. I possess a case of this 

 species, to the outside of which is affixed the empty shell of 

 a beech mast. The larvae inhabited a dike under a beech 

 tree, and these empty shells seemed a favourite substance with 

 them, as I observed many marching about thus adorned. 

 L. vittafus and centralis, &c., form narrow, often somewhat 

 curved tubes, composed of sand and small stones. The genus 

 Anabolia also constructs portable cases, and that of the com- 

 mon A. nervosa is somewhat similar to that of L. vitratus, 

 but it displays less eccentricity in the substances that it attaches 

 to the outside of its case. In Stenophylux, the perfect insects 

 of which are closely aUied to Anabolia, the case differs from 

 that genus in not being entirely free, and, as might be expected 

 from this peculiarity, the larvae inhabit running streams. The 

 cases of the various species probably differ little one from the 

 other. They are straight, and composed of small usually 

 angular stones, slightly lai-ger at one end, and affixed by one 

 extremity either vertically or horizontally. In Malesus the 

 larva of J3". digitatus forms its case of vegetable matters, ar- 

 rano^ed lonixitudinallv like tiles, but I am inclined to believe 

 that the larvce of the smaller species form habitations similar 

 to those of Slenophylax. Choetopteryx constructs a case of 

 vegetable matters, arranged longitudinally and irregularly. 

 Enoicyla pusilla affords the only instance at present known of 

 a Trichopterous insect with a terrestrial larva. It forms cases 



