430 THE HETEROPTERA. 



Several other species, such as the Polish Scarlet Grain {Coccus polo?iieus), and the 

 Kermes {Coccus ilicis), arc also valuable to colorists, and impart a very fine scarlet to sub- 

 stances treated with them, although the hues are not equal to those obtained from the cochineal. 

 The latter of these insects was known both to the Greeks and Romans, and was used by them 

 for the purpose of obtaining the purple dyes which were so much worn by the higher classes. 



The Lac Insect (Coccus lacca) is another member of this most useful genus. This species 

 resides in India and the hotter parts of Asia. It is found attached to the twigs of trees, and 

 is then called stick lac, the shell-lac being the waxen secretion purified and shaped into thin, 

 shell-like plates. 



The Grape Phylloxera ( P. vitifolicB) is the most destructive of the Aphides. Though first 

 characterized in Europe, North America seems to lie the home of the genus, for, while there 

 are but two well-defined species so far known in Europe, sixteen distinct species are found in 

 various parts of the United States. They are gall-inhabiting creatures. For a long period 

 the Phylloxera was only an object of interest to the naturalist ; hut, five or six years since, the 

 Grape Phylloxera came suddenly to lie a creature of great concern to the public. Indeed, this 

 species has become so prominent that it is entitled the Phylloxera, though fifteen other species 

 are known. It is found from Canada to the Gulf States, and east of the Rocky Mountains. 



Early in the history of the grape culture in the United States, the gall-making type was 

 observed on the leaves of certain varieties, particularly on the Clinton, and in 1856 this was 

 briefly described by Dr. Fitch, State Entomologist of New York, by the name Pemphegus riti- 

 folice. The more normal root-inhabiting type was not suspected, however, until it was dis- 

 covered by Prof. Filey, of Washington, in 1871. A kind of grape-root disease began to show 

 itself in France, where the grape interest is of vast importance. Large sums were offered by 

 the government. It was found eventually that it was the identical species that is indigenous 

 on American vines, and that it was imjDorted into France from America, probably during our 

 civil war, on our vines sent to French nurserymen. It presents two forms or types, the root- 

 eating and the gall-inhabiting. The insect is about a sixteenth of an inch in length. The 

 appearance of the vine-roots, after being infested, is that of a collection of young potatoes 

 just formed. There seems no practical remedy for the vines already affected. The only ser- 

 viceable practice is to substitute new vines ; and though America furnished the enemy, yet it 

 is found that the American vines resist the pest much better than those of France. Conse- 

 quently, the vineyards of the Old World are being replanted by vines shipped from our 

 American vineyards. The Cunningham, Norton's Virginia, Clinton, Concord, Taylor, are 

 preferred. Those especially preferred are of the species cestiralis, as Herbmont, Cynthiania. 

 The French have now learned to appreciate our vines, when formerly they scorned the idea of 

 importing them. American grape culture, meantime, is advancing favorably from this com- 

 munication of the culturists of both countries. 



HETEROPTERA. 



The insects belonging to the large and important order which is placed next to the 

 Homoloptera, are readily known by several conspicuous characteristics. The wings are four 

 in number, and the front pair are very peculiar in their structure, the basal portion being- 

 horny, like the elytra of beetles, and the remaining portion membranous, like the hinder 

 wings of the same insects. In some species, however, the wings are wanting, as in the common 

 Bed-bug (Cimex lectularius). The body is always much flattened, the mouth is beak-like, 

 and in the pupal stage the creature is active and resembling the perfect insect, except in its 

 want of wings. 



As the space which can be devoted to the remaining insects is extremely limited, it will 

 lie merely possible to give a brief sketch of the different families. 



