. Annual report. Entomological Society of Ontario; Insect pests; Insects -- Ontario Periodicals. 55 had been at its destructive work for yenrs, producing injury the true cause of which was never suspected until the publication of the article in my fourth Keport. I also showed that some of our native varieties enjoyed relative immunity from the insects! attacks, and urged their use for stocks, as a means of re-establishing the blighted vineyards of Southern ; " The disease continued to spread in Europe, and became so calamitous in the last- named country that the French Academy
. Annual report. Entomological Society of Ontario; Insect pests; Insects -- Ontario Periodicals. 55 had been at its destructive work for yenrs, producing injury the true cause of which was never suspected until the publication of the article in my fourth Keport. I also showed that some of our native varieties enjoyed relative immunity from the insects! attacks, and urged their use for stocks, as a means of re-establishing the blighted vineyards of Southern ; " The disease continued to spread in Europe, and became so calamitous in the last- named country that the French Academy of Sciences appointed a standing Phylloxera Com- mittee. It is also attracting some attention in Portugal, Austria and Germany, and even in England, where it affects hot-house grapes.' Natubai, History of the Insect. The genus Phylloxera is characterized by having three-jointed antennas, the third or terminal being much the longest, and by carrying its wings overlapping, fl it on the back in- stead of roof-fashion. It belongs to the sub-order of whole-winged bugs (llomopiera), and forms a connecting link between two of its great families, the Plant-lice(yl/)/HV//rfa;) on the one hand, and the Bark-lice {Coccidce) on the other. It is generally considered, however, to pertain to the former family, though some naturalists, with the not uncommon love of intro- ducing new names and minute classifications, have desired to found a new family for this special insect. Not the least interesting feature in the economy of the Phjlbxera is the different phases or forms under which it presents itself Among these forms are two constant types which have led many to suppose that we have to do with two species. The one type, which for convenience Mr. Rile\- terms ga/kvcda, lives in galls on the leaves; the other which he calls radicicola, lives on swellinjjs of the roots. They may be tabulated thus : — Type 1. Oaihecola (see Figure 43,/, g, /;), Type 2. Radicicola. A, Degraded or wingless for
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectinsectp, bookyear1872
