Labrador, the country and the people . omes within reachof its extensible lower lip, which is armedwith a pair of jawlike hooks. They arevoracious feeders and not at all particular,for young fish are frequent victims. Theyare, however, to be classed among the Nymph of the msects, tor they undoubtedly destroy great numbers of the pestiferous gnats, mosquitoes, andflies. After moulting several times, the nymph, when it attains itsfull size, crawls out upon some stick or plant, the skin splits longi-tudinally along the back, and the adult dragon-fly emerges. Thelife of the a
Labrador, the country and the people . omes within reachof its extensible lower lip, which is armedwith a pair of jawlike hooks. They arevoracious feeders and not at all particular,for young fish are frequent victims. Theyare, however, to be classed among the Nymph of the msects, tor they undoubtedly destroy great numbers of the pestiferous gnats, mosquitoes, andflies. After moulting several times, the nymph, when it attains itsfull size, crawls out upon some stick or plant, the skin splits longi-tudinally along the back, and the adult dragon-fly emerges. Thelife of the adult is from twenty to forty days, depending on cli-matic conditions, the more northern latitudes being three hundred species are known from the whole of NorthAmerica, of which only eight have thus far been collected in Labra-dor, including such large and widely distributed species asMshna constrida (PL, Fig. 15), AiJ. crenata, M. septentrionalis, thetype of which was from Labrador, four species of the genus Somato-. FiG. 14. 440 APPENDIX I chlora, two of which were originally described from this region,and Leucorhina hudsonica (PI., Fig. 16). The May-flies, or day-flies, belong to the order Ephemerida,an application which refers to the short lives of the imagoes. Theyrepresent one of the more primitive groups, with mouth-partsrudimentary or almost wanting in the adult, as they do not feedduring their few hours of existence as winged insects. The wingsare delicate, with a fine network of veins; the hind wings are muchsmaller than the fore wings, or sometimes wanting; the abdomenbears two or three long, many-jointed, bristlelike appendages,while the antennae are very short. Inthe nymph or the wingless aquatic stagetheir life is a long one, in some speciesoften extending to two or three nymphs are interesting objects ofthe streams and lakes, clinging to theunder sides of stones and sticks and feed-ing on the smaller animal and plant are read
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