PSYCHE. 



CADDIS-WORMS OF STONY BROOK. 



BY CORA H. CLARKE, JAMAICA PLAIN, MASS. 



That part of Stony Brook in which I 

 have made collections lies within the 

 limits of the City of Boston. It is about 

 eight feet wide, and its depth varies 

 from two to twenty-four inches. In 

 some places it flows slowly, in others 

 rapidly ; here the bottom is muddy, there 

 pebbly. Fresh-water algae of several 

 species, a great variety of other water 

 plants, and many different animals are 

 found in it ; among the animals are 

 fresh-water sponges, Polyzoa, plan- 

 arians, mollusks, water insects of all 

 kinds, and occasionally a fish, newt, or 

 turtle. But the most interesting of all 

 its inhabitants are the larvae of the 

 Trichoptera or Caddis-worms. I have 

 found in all about twenty distinct species, 

 representing each of the seven families. 



Phryganeidae. Of this family I 

 have found only only one representa- 

 tive, a species of Neuronia. Possibly it 

 is jVeurom'a stygipes, but the only 

 imago which I have succeeded in rear- 

 ing was imperfect. It emerged from the 

 aquarium on April 5th. The larva has 

 a yellow face striped with black, and is 

 very restless and nervous in its move- 

 ments, continually travelling about the 

 aquarium, making sad havoc among its 

 inhabitants, eating dragon-fly larvae as 

 large as itself, other caddis worms, and 



Fig.i. 



indeed any insect which it can catch. It 

 also devours raw beef with relish. The 

 case of this larva (fig. 1*) is 

 made of quadrangular pieces 

 of leaves, fastened together 

 by their edges and arranged 

 in rings rather than in the 

 spirals which M'Lachlan 

 tells us is characteristic of 

 the genus. Three or four or 

 sometimes more of these rings, make 

 the length of the case, which, when full- 

 grown, may be 35 mm. long.f When 

 the Neuronia larva is not satisfied with 

 its case it bites off a ring at one end, 

 replaces it with a freshly constructed 

 ring, and then turns within the case, and 

 does the same at the other end. If 

 pushed out of its case, and deprived of 

 it, it will make a new one in a night. 

 Sometimes this species is tolerably abun- 

 dant, and again for several years, it is 

 quite scarce. 



Limnophilidae. I have found five 

 or six species of this family. The 

 commonest of these is Hallesus maculi- 

 fiemiis, the larvae of which are very 



* All the cuts are of the natural size excepting fig. 2^ 

 and the operculum in fig. S. 



f I have found that with most species of caddis- 

 worms the case of the pupa or adult just before pupat- 

 ing isjshorter than that of the growing larva. 



