S48 NATURAL HISTORY 



story is a pure rnyth. The point has been settled by direct observation. A not uncommon North 

 American species (Oncideres cingulatus), called the "Hickory girdler," is known to saw branches of 

 the hickory-tree (Carya alba} in the manner we have described, and its habits have been carefully 

 studied by Professor Haldemaii. Our figure represents a larger species (Oncideres vomicosus) not 

 uncommon in Brazil. 



TRIBE PHYTOPHAGA. 



The Phytophaga, the third and last tribe of the great Tetramerous division, are, as a rule, 

 distinguishable from the Longicornia (with which they agree in the absence of the snout-like 

 prolongation of the head which characterises the Rhynchophora) by the shorter body and antenna?, 

 and the brightly-coloured and polished integuments. In habits they differ by living only on 

 the foliage of plants, not on the wood or fruit ; and they are, with the exception of one genus 

 (Cyrtonus), diurnal in their period of activity, having in consequence finely-faceted eyes. So close, 

 however, is their relationship to the Longicornia, that there is no single structural character to be 

 pointed out as applicable in all cases for distinguishing the two tribes. In nearly all the species the tarsi 

 are short and broad, with the third joint bi-lobed or heart-shaped, and the rudimentary or functionless 

 fourth joint always visible at the base of the claw-joint ; beneath, the joints 1 3 are furnished with 

 flat brush-like palms, which enable the insects to walk with ease, even back downward, on the under 

 surface of leaves ; and the claws are very often adapted for clinging to the edges of foliage, either 

 by their position, or by being more or less toothed on their inner sides. 



Although so closely allied in structure in the adult form, the Longicorns and the Phytophaga are 

 strongly contrasted in their larva stage. The larvae of the Phytophaga are nearly always of short and 

 convex form of body, rarely sub-cylindrical or depressed, and of firm leathery texture, sometimes 

 metallic-coloured like the perfect insects. Their abdominal segments are frequently provided with fleshy 

 or scaly tubercles, or spines and bristles, and the anal one is prolonged beneath into a retractile tube, which 

 is used in walking. In all cases they live on the same food, and generally on the same species of tree 

 or shrub, as the perfect insect. On the same plant the eggs are laid, and in numerous cases, where the 

 species infest cultivated grounds, their great and rapid multiplication during the summer months 

 renders them the most injurious of all insect pests to the farmer and gardener. The famous Colorado 

 Potato-beetle, which increased so suddenly, and created such devastation in the United States ;i 

 few years ago, and seemed likely to cross the Atlantic, to the alarm of the agriculturists of "Western 

 Europe, belongs to the family, as does also the ' : Turnip-jack," the plague of the British farmer. One 

 numerous class of the larvje (belonging to the Hispinse and Halticinae sub-families) are miners, i.e., 

 they live within the cuticles of leaves, devouring the parenchyma, and undergoing their transformations 

 in the same confined space. Another large group (belonging to the sub-families Criocerince and 

 Cassidinve) live exposed on leaves, and have the remarkable habit of concealing themselves with their 

 own excrement, which is retained and secured by a special horny apparatus at the end of their 

 bodies. In the typical groups of Chrysomelince and Eumolpinm, the larvae feed at large on plants, and 

 bury themselves in the earth previous to changing into the pupa stage. 



The Phytophaga are divided into four sections, which are nearly equivalent to the families of 

 other tribes. The first of these, the EUPODA, approach nearest in their general form, as well as in 

 their structural characters, to the Longicomia and the family Bruchidse of the Rhynchophora. Among 

 them are the large brilliantly-metallic Sagm, or Kangaroo-beetles of tropical Asia and Africa, 

 remarkable for their greatly-enlarged hind legs ; the Donation, elegant insects of similar form, but 

 smaller and of less brilliant colours, which live on water-lilies and other aquatic plants chiefly in 

 north temperate climates, nineteen species being found in the British Islands. They pass their early 

 stages amongst the roots of the same plants ; and the Criocerince, of which there are several British 

 species the principal being Crioceris merdigera, of uniform brownish tint parasitic on lilies, and the 

 prettily-spotted C. asparagi, found abundantly on asparagus plants in the south of England. The 

 second section are the CAMPTOSOM.E, characterised by the strong curvature of the ventral segments of 

 the abdomen, by which the three middle ones are much contracted. To this belongs a large series of 

 genera, having usually a compact oval or oblong form of body, and extremely varied colours, 

 polished metallic coloration being less the rule than buff, yellow, and red, spotted or striped with 

 darker hues. The British species best known of this section are the Clythra tridentata and 



