. Annual report of the Regents . Fig. 9.—The pear-treePsylla, Psylla pyri-cola, male. check to its further few years, its ex-cessive multipli-cation seems to operate as aincrease, and to consign it foranother term of years to insignifi-cance in numbers and Fig. 10—Wings of the pear tree Psylla; c,clavus; c. «., claval suture; s, stigma. Ninth Befori of the Si ate Entomologist 319

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