. Class book of economic entomology, with special reference to the economic insects of the northern United States and Canada. Beneficial insects; Insect pests; Insects; Insects. 128 ECONOMIC ENTOMOLOGY hatching in June-July, the Forbes Scale (A. forbesi John.), and the Curtis Scale (A. osfreceformis Curtis) (Fig. 79), are difficult to dis- tinguish from the San Jose Scale, and are also found in orchards. A comparison of the pygidium, or the fused posterior abdominal seg- ments, under the microscope enables one to identify the adults of these species. On the dorsal surface of the pygidium are t
. Class book of economic entomology, with special reference to the economic insects of the northern United States and Canada. Beneficial insects; Insect pests; Insects; Insects. 128 ECONOMIC ENTOMOLOGY hatching in June-July, the Forbes Scale (A. forbesi John.), and the Curtis Scale (A. osfreceformis Curtis) (Fig. 79), are difficult to dis- tinguish from the San Jose Scale, and are also found in orchards. A comparison of the pygidium, or the fused posterior abdominal seg- ments, under the microscope enables one to identify the adults of these species. On the dorsal surface of the pygidium are the anal opening and the glands that secrete the wax of the scale. On the ventral sur- face are the vaginal opening and 4 or 5 groups of spinnerets (wanting in the San Jose Scale). The margin of the pygidium is modified into. A B C Fig. So.^Three common orchard scales. A, San Jose scale; B, oyster-shell scale C, scurfy scale. lobes with thickenings, dorsal and ventral spines, and plates character- istic of each species (Fig, 79). Euonymus Scale {Chionaspis euonymi Comst.) is a common pest of Euonymus in the Eastern United States. Two broods a season. Female scale elongate-oval, brown, with yellow exuvia, convex; male scale white, parallel-sided, 3-ridged, with yellow exuvia, much smaller than female scale. Rose Scale {Aiilacaspis rosa Bouche).—Attacks rose, raspberry, blackberry, etc. Female scale snow-white, nearly circular, thin and flat, 3^-12 i^ch in diameter; with two light yellow exuviae at margin; oviparous. Male scale shorter, narrower, 5-ridged. Hibernates in all stages, hence all stages may be found on one infested plant. Two or three broods a. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Lochhead, William, 1864-1927. Philadelphia : Blakiston
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectinsects, bookyear1919
