British medical journal . ll lately, and, indeed, at thepresent moment many English villages are still blissfullyignorant of this particular nuisance. As Fig. 2 shows, the cockroach is a somewhat slacklyput together insect. One might almost call it i-atherslatternly and loose-jointed—and the latter it certaiuly i?:.Its head moves freel3- on the thorax and the thorax on theabdomen. The successive segments of the latter movevery freely on one another. The legs are long and mobile,and so are the antennae with whioh tlie is cease-lessly testing the ground over v,hich it flits hither andthi
British medical journal . ll lately, and, indeed, at thepresent moment many English villages are still blissfullyignorant of this particular nuisance. As Fig. 2 shows, the cockroach is a somewhat slacklyput together insect. One might almost call it i-atherslatternly and loose-jointed—and the latter it certaiuly i?:.Its head moves freel3- on the thorax and the thorax on theabdomen. The successive segments of the latter movevery freely on one another. The legs are long and mobile,and so are the antennae with whioh tlie is cease-lessly testing the ground over v,hich it flits hither andthither in a restless activity. Cockroaches are very difflcult to catch. They practi-cally never walk, but run with a hardlj believable rapiditj-,darting hither and thither in an apparently erratic modeof progression. When caught they are not easily retained,for they have all the slipperiness of a highly-polishedbilliard-ball. They have great powers of flattening theirbodies, and the3- slip out of ones hand with an amazing. Fig. l.—VeriitXanela orientalis, male, x 2. Side view. (Prom Eiiliontbal.) ;2. head; 3, prothorax: 4. anterior wing: 5, soft skin between tcrga and sterna: 6. sixthabdominal ter^nm; 7. sjilit portion of tenth abdominal tersnm: 8, cerci anales; 9, stj-les;10, coxa of third leg; U, trochanter ; 18. femur; 13, tibia; 14, laisus ; 15, clavra. o£ dexterity. Besides their slipperiness they have anotherweapon, and that is a wholly impleasant and most in-tolerable odour, which is due to the secretion of a c-oup!cof glands situate on the back of the abdomen. The glandswhich produce this repellent odour arc sunk in the softmembrane which unites the fifth and sixth abdominalsegments, and the moment a cockroach is attacked itexudes a sticky, glue-like fluid, which gives out this mostunpleasant smell. The fluid is extraordinarily tenaciousand difficult to remove from the hand of those who have ,_-,Q TnuBniTisa 1 lUUO JjEDlCAl, JOCBHAL J COCKROACHES. [Dec. 12,
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Keywords: ., bookcentury1800, bookdecade1850, booksubjectmedicine, bookyear185
