INSECTS. 331 



from South America, and which belongs to a different 

 genus." [E. T. Cresson, Mss. 



These moths may yet become valuable for the produc- 

 tion ot a kind of silk, as they are enclosed in large co- 

 coons, the fibres of which surpass those of the Silk-worm 

 in strength, and might be employed in the formation of 

 fabrics, similar to those manufactured in India from the 

 Tusseh and Arrindy Silk-worms, the strength and dura- 

 bility of which are proverbial. Mr. Pullein, who experi- 

 mented with the cocoons of the Cecropia, found that 

 twenty threads of this silk, twisted together, would sus- 

 tain nearly an ounce more in weight than the same num- 

 ber of common silk. (Vide Harris, pp. 295-303.) 



Psychidce are curious caterpillars, which, being naked, 

 cover themselves during the larva state with a case that 

 protects their bodies, though open at both ends, and which 

 thoy carry about with them ; these cases are made up of 

 fragments of leaves, generally the stems and veins, which 

 they connect together by threads of silk. The Germans call 

 them Sack-bearers. Huebner called them Cancephorce, or 

 Basket-carriers, because the cases, often made of little 

 sticks, resemble a basket. One genus is called CEceticus, 

 or House-insect ; and the common species, which, in some 

 parts of the country, commits great devastation upon the 

 leaves of trees, is called the Drop-worm, or the Basket- 

 worm, in many places. 



We have several genera and species belonging to this 

 sub-family, the most common of which are the Thyridop- 

 teryx ephemeraformis, and (Eceticus coniferarum. The 

 best means for the destruction of this pest consist in per- 

 severing efforts for their individual destruction ; each case 



