Page:Jardine Naturalist's library Entomology.djvu/87

Rh forwards. Maxillæ are sometimes wanting, (as among many dipterous larvæ,) but when present they are placed immediately under the upper jaws, and are more or less subservient to mastication. They are generally without the lobes which distinguish the corresponding parts of the imago, but there is, for the most part, a palpiform process, analogous to the internal maxillary palpus, or what is called galea in the orthoptera. Palpi exist in all larvæ save dipterous and hymenopterous ones, but they are often short and inconspicuous. The maxillary palpi are sometimes four in number, at other times only one is attached to each maxilla; the labial palpi are always limited to two. Their shapes are conical, setaceous or filiform; the joints variable in number, and not unfrequently branched. The upper lip presents nothing peculiar, but the under lip, in the tribe of dragon-flies, (Libellulidae,) assumes a very singular form, as will be seen when we come to specify the peculiarities of the order Neuroptera. In connection with the under lip, there is an instrument peculiar to some larvæ, namely, a spinneret—a small conical tube through which the silken threads are drawn, which are so indispensable to the economy of a large proportion of them. The antennæ are far from presenting that variety of design and beauty of structure which render them, not unfrequently, very ornamental appendages to insects in a state of maturity. They are often entirely wanting, (as in the maggots of many two-winged flies, bees, &c.) and frequently so minute, that even when they do exist, they cannot easily be