4 LAKV^ OF THE PEI0:NIN^. 



than one identified species on which to base the characters of a given 

 genus. For this reason the key is purely artificial and only in part 

 applicable to the other congeneric species. ^ 



During the past two years the writer has carried through to imag- 

 ines larvae from all available sources. This has resulted in the 

 identification of some 200 additional species, making available the 

 large amount of heretofore unidentified material in the forest insect 

 collection. 



Great care is needed in the methods of rearing these larvae. Often 

 a single piece of infested wood will contain from five to a dozen 

 different species of Cerambycidse. It has sometimes occurred that 

 adults and larvae which have been found together in the wood have 

 been wrongly associated by the collector, and the larvae have been 

 preserved in the collection under the name of the adult. As a 

 matter of fact, however, it is more often the case that larvae and 

 adults which have been found together are of different species rather 

 than of the same, because the greater part of a brood of one species 

 generally transforms about the same time. My practice has been 

 to cut the larvae out of the infested wood, separating the species as 

 nearly as possible, and then to cage each larva individually. As 

 the adult emerges the larval skin is preserved for careful comparison 

 with the alcoholic specimens. Many methods have been tried for 

 proper preservation of the material. The most satisfactory for all 

 purposes is to kill the specimens by boiling in water for from 5 to 10 

 minutes, according to size, and then place them in 75 per cent alcohol. 

 This gives especially good results for anatomical work. Whiter 

 specimens may be had by placing in a mixture of strong alcohol 

 and a small amount of acetic acid for a few minutes, or by killing 

 in a boiling solution of this mixture. The latter method, however, 

 often interferes with a subsequent study of the muscles. 



The larvae of Cerambycidae are primarily and probably without 

 exception phytophagous, boring in the ligneous tissue of, for the 

 most part, the arborescent flora, though a few species are confined 

 to herbaceous plants, in this case being usually pith or root feeders. 

 Some are confined to one species of tree, as is usually the case 

 with those attacking living tissue, others to a single genus, and 

 again there are species which will have a wide variety of host plants 

 among either the conifers or the hardwoods, but the larvae of the 

 same species will rarely attack both indiscriminately. 



Great diversity is shown in the feeding habits and larval mines. 

 Some species bore exclusively in decayed moist wood, others in dead 



1 The writer is desirous of securing other larval material in this family from aU sources, especially such 

 genera as Derobrachus, Stenodontes , and species of Prionus not treated in this paper. Collections will 

 be gladly looked over and material determined. Exotic material is also much desired, and exchanges will 

 be made.— F. G. C, Bureau of Entomology, U. S. Department of Agriculture, Washington, D. C. 



