. British insects : a familiar description of the form, structure, habits, and transformations of insects. a Head of Tiger-beetle, (magnified) with jaws Ditto, with jaws open. midable pair of pincerswhen extended as in thefigure (6), and lying quiteacross each other whenclosed (a). These organsare even larger and moreconspicuous in the male ofthe Stag-beetle, whilst inmost other beetles theyare much smaller and lesspowerful. The second pair of jaws,or the maxillee (fig. 4), aremore complicated anddelicate. The principalparts of the maxilla are a kind of blade {a), fringed with hairs,
. British insects : a familiar description of the form, structure, habits, and transformations of insects. a Head of Tiger-beetle, (magnified) with jaws Ditto, with jaws open. midable pair of pincerswhen extended as in thefigure (6), and lying quiteacross each other whenclosed (a). These organsare even larger and moreconspicuous in the male ofthe Stag-beetle, whilst inmost other beetles theyare much smaller and lesspowerful. The second pair of jaws,or the maxillee (fig. 4), aremore complicated anddelicate. The principalparts of the maxilla are a kind of blade {a), fringed with hairs, and an antenna-likeFig. 4. Fig. 5. feeler or palpus (6), called the maxil-lary palpiis. Inthe Tiger-beetle andsome other preda-ceous beetles thereis a second appen-dage (c) resemblinga less developed pal-pus. The upper lip is ahorny plate, withoutappendages. The lower lip, or la- 4. Maxilla of Tiger-beetle (highly magnified), i^ • „ ^ /ft o- ^-s ,• „ „p„^ 5. Labium of Tiger-beetle. ^°^ v^g- ^J, IS very. EXTERNAL STRUCTURE OF INSECTS. 31 different in diflferent orders of insects. It is composedof several pieces, more or less developed, and boththese separate pieces and the wbole organ have beenvariously named by various authors. It is generallycomposed of a basal horny plate, succeeded by asecond horny or membranous plate, something likea lip, or by a prolonged fleshy tongue-like organ;and always bears a pair of palpi, called labial palpi(fig. 5, a a, and 6, //). Sometimes the whole organis called tbe labium or lip, sometimes only the secondpart is so called, the first being called mentum or tbe whole is called lip, tongue, pro-boscis, and so on. In the present work the whole organwill generally be called by the most usual name oflabium, while the English words lip, or tongue,will be applied according to the form, whether it be, asin beetles, for instance, a lip-like plate, or, as in bees, afleshy projectile tongue-like instrument. In the dragon-fly a
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Keywords: ., bookauthorme, bookcentury1800, bookdecade1870, booksubjectinsects
