ENTOMOLOGY

396 SANITAR Y ENTOMOLOGYFIG. 74.-Bedbug: Egg and newly hakhed larva: a, Larva from below; b, larva fromabove; c, claw; d, egg; e, hair or spine of larva. Greatly enlarged, natural size oflarva and egg indicated by hair lines. (Marlatt.)FIG. 75.-Bedbug: a, Larval skin shed at first molt; b, second larval stage immediatelyafter emerging from a; c, same after first meal, distended with blood . . Greatlyenlarged. (Marlatt.)The life cycle in Cimex hemipteru8 and C. lectulariu8 has been demonstratedby Patton. The parasites are ingested by the bug, enclosed inthe large cells or leucocytes, and develop into fully flagellated formswithout reference to the temperature of the external air. The sizeincreases from 4 to 7 micra and vacuolation of the cytoplasm occurs onor after the second day. The single parasite may proceed directly toflagellation, by the appearance of an area stained bright pink by Giemsasolution and called the flagellar vacuole. This vacuole which has a darkcenter rapidly increases in size up to 1 to g micra and, passing to thesurface, sends out a pink brush which forms the flagellum by merelygrowing longer. The flagellate form has a dark blue, granular cytoplasmwith a circular trophonucleus which stains deeply in the center; and a.kinetonucleus lying across the long diameter and situated near the