49 



RHYNCHOPHORA— WEEVILS. 

 W. Hague Harrington, Ottawa. 



The weevils are beetles belonging to that division of the Coleoptera known as Tetra- 

 mera in the classification of early authors, and so distinguished because the beetles in- 

 cluded in it have apparently only three-jointed tarsi or feet ; the penultimate joint being 

 so small and so closely connected to the preceding one as to be invisible without a mag- 

 nifying glass. The greater number of these beetles can be readily separated from those 

 of other families by their snouts or beaks, which in many species are so elongated and 

 attenuated as to give their bearers somewhat of the appearance of lilliputian six-legged 

 elephants. (See figure 31, which represents the apple curculio, Anthonomus 

 quadrigibbus.) This well marked feature in their structure has gained for 

 them their common name of " snout-beetles," and their scientific appellation 

 of Rhynchophora, derived from the Greek, and signifying " beak-bearing." 

 If we carefully examine one of these insects we will see that the head is 

 lengthened into a proboscis, at the end of which are situated the mouth-parts, 

 Fig. 31- so reduced in size as to be almost invisible to the naked eye. 



On the sides of the rostrum (to use the scientific name for this proboscis) are set the 

 antennae, usually slender and long ; sharply geniculated or elbowed in many species, 

 and commonly knobbed. They can be folded back so closely against the base of 

 the snout, which is often grooved to contain them, as to be quite hidden. The beetles 

 have hard, rounded bodies ; some love the sunshine, others lie hidden all day and when 

 night falls creep forth from their hiding places to continue their depredations, or fly about 

 in search of new fields. The legs are often short and not well fitted for rapid progress, or 

 for digging. Many have ample wings to carry them about, but in some species these use- 

 ful appendages are wanting, or are so short as to be useless as organs of flight. 



So far as known to me all the snout-beetles are vegetable feeders, and the great 

 majority of them may be styled "obnoxious insects"; many being veritable pests to agri- 

 culturists and arboriculturists. They attack trees and plants of every kind and in every 

 part ; roots, stems, bark, twigs, pith, leaves, buds, flowers, fruits and seeds are all subject 

 to the depredations of these long-headed foes, which, though minute, exist in such 

 countless numbers as to make the total loss inflicted by them severely felt. 



Weevils when young are short, fleshy, whitish grubs, without legs, and effecting 

 what slight progress they require by the aid of their hunched segments, by the shape of 

 which they may be easily known from the maggots of flies. Their heads are scaly or 

 horny, and furnished with sharp mandibles to nibble the hard substances in which so many 

 of them dwell, and in which they thus construct cells or short burrows. In these cells 

 the majority of species pass also the pupa state, emerging only as fully developed beetles 

 to spend a brief existence in the outer world. It is in the grub state that the weevil 

 commits its depredations, for then it is invariably concealed in that part of the plant on 

 which it subsists, secure despite its utter helplessness, and finding its proper nutriment in 

 the walls of its prison. Trees are stunted and warped by having their young shoots de- 

 voured ; fruit and nuts are caused to drop prematurely and decay ; rice, corn, wheat and 

 other cereals become mere empty husks, while peas, beans, and a great variety of seeds 

 are destroyed by enemies so tiny that the hollowed shells form the house in which the 

 full grown larva transforms to a perfect insect. 



Our own weevils are inconspicuous both in size and colouring ; in fact nearly all of 

 them are small and dull looking beetles. In tropical countries, however, snout-beetles are 

 found of very formidable dimensions, and some are most brilliantly marked and painted ; 

 of these I will mention a few examples presently; 



The Rhynchophora are divided into two families, the B ruchidai and the C urculionidce 

 (which unwieldy family has recently been subdivided into several smaller ones, but the 



4 



