142 PKOC. KNT. SOO. WASH., VOL.. 54, NO. 3, JUNE 1952 reduced. The other method, as was mentioned, is by forcible extrusion. If the midrib of the papaya plant is pierced with a needle, a large drop of sap is instantly forced out of the puncture by pressure within the plant. This sap is very different in ap-pearance from the honey-dew which appears at the tip of the abdomen of the membracids, being whitish and milky. Within a few minutes it coagulates or congeals to form a soft, white, starch-like ball. Certainly, feeding by the nymphs must be effortless, with unlimited food supplied and that under pres-sure. In fact, the life of this membraeid, from egg to death, is one of idyllic indolence. No movement is necessary except-ing that of crawling out of the egg shell, attaching the mouth-parts once and for all to a never-ending food supply, up-ending the abdomen (when caressed) for the automatic re-moval of excrement, shedding the old clothes (with new ones already present beneath ! ) , and mating. Females, ' ' the over-worked sex, ' ' have only the additional labor of laying eggs in the tissues of the plant. A NEW SPIDER MITE (ACARINA, TeTRANYCHIDAe) By E. a. McGregor, Collaborator, Bureau of Entomologi/ and Plant Quarantine, U. S. Department of Agri-culture. This paper contains the description of a new tetranychid mite from Arizona. The type material is deposited in the U. S. National Museum, Washington, D. C. Tetranychus frosti, new species Female. — Dorsum of alKloineii with striations mostly transverse (the "*' Eotetranychus" type). Twenty-six dorsal body setae, well developed, linear lanceolate, distinctly setose, not arising from tubercles. A per-fect and an imperfect eye cornea each side. Legs shorter than body to front of cephalothorax. Tarsus I with two sets of duplex setae, these proximate, longest seta almost as long as segment; 6 (occasionally 7) setae proximad of proximal set of duplex setae; segment abruptly con-stricted distad of duplex setae. Relative length of segments of leg I as follows: Coxa, 14± ; trochanter, 10; femur, 24; patella, 12; tibia, 16; tarsus, 23. Mandibular plate barely indented anteriorly. Claw of tarsus I deeply cleft into six rather delicate divisions, these appressed right and left. Palp-tarsus with basal thickness distinctly greater than axial length; terminal sensilla somewhat longer than thick; dorsal sensilla very slender. Collar trachea consisting of a straightish tube, terminat-ing internally in a few thickened septa, the last at times forming a very short, reflexcd arm.
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