Page:Jardine Naturalist's library Entomology.djvu/109

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ENTOMOLOGY.
103

be regarded as divisible into four parts: the insertion or hinge, (cardo) which is the lowest portion by which it articulates with the throat, and which is usually placed nearly at right angles with the following part. The latter is the stalk, (stipes) generally pretty strong and thick, at least in its upper part, although frequently it is soft and membranous beneath. Attached to this, on its outer side, is a small portion which has been named the feeler-bearer (squame palpifère of Strauss,) because the maxillary palpus is always inserted on its outer edge. The terminal portion of the maxilla, which usually appears in the shape of a hook,[1] ciliated on its inner edge, and frequently toothed at its extremity, is the maxillary lobe, (internal lobe of Latreille, lacinia of Macleay.) This, which is an important part, as it acts immediately upon the food, is very often simple, but at other times it is divided into two pieces, in which case the one is called the external, the other the internal lobe of the maxilla. The external lobe is sometimes called the galea or helmet, (this is its appropriate name among the Orthoptera) but when it is jointed and palpiform, as it frequently is among the carnivorous Coleoptera, it is commonly described as the internal maxillary palpus. The maxillary palpus properly so called, is a pretty long, jointed, commonly filiform process, the presence of which always distinguishes the maxillæ from the mandibles. The

  1. The lobe of the maxillæ is occasionally terminated by a moveable claw, as may be seen in certain Orthoptera and the tribe of Cicindelidæ or tiger-beetles.