of necessity several genera of these insects, we

Omitting come to one which is among the most destructive of the group. This is the Eice Weevil (Sitophilus oryzce), which is shown on Woodcut XIX. Fig. 5. The generic name of Sitophilus and is given to the insect on account of signifies ‘ grain-lover,’ the terrible havoc which it makes in corn-stores. It belongs of which there is only one British to the family Calandridse, just been mentioned. In this family the

genus, that which has have eight ..joints, the last joint being large and

antennse The body is rather flat, and the elytra, which are

rounded. do not quite cover the end of the abdomen.

boldly striated, is another species, the Corn Weevil {Sitophilus grana-

There feeds upon corn as the present species does on

nus), which is distinguished by having four red

rice. The Eice Weevil on the elytra, the Corn Weevil being altogether duskyred. spots

Like tlie Nut eevil, these insects do their destructive work

in secret, and there is no finding out the mischief until it is too late. The mother Weevil — tiny herself — inhabits a tiny hole in a grain of corn, and therein deposits a single egg. The larva is soon hatched from the egg, and sets to work at feeding in the interior of the grain, the whole of which it consumes, leaving the exterior untouched, so that the grain appears quite sound. Of course, the damaged grain is lighter than the sound one, the body of the larva not compensating in weight for the amount of substance devoured by it; and, if the corn be thrown into water, the damaged corn will rise to the surface, and may be skimmed off and burned. As, however, damaged corn and rice can both command a sale, and as all damaged grain is not attacked by the Weevil, the dealers will seldom employ such a ineasme ; though to destroy all the light corn for the

tlie Weevils to

The destruction wrought by these tiny foes can scarcely be over-estimated, but some idea of it may be estimated from the follomng statements which were made at the Entomological Society, April 4, 18?0. Seventy-four tons of Spanish wheat had been carefully sifted or ‘ screened > to separate^ the Weevils were wZ sitted. sfflS Agat*^'' ^ hundre^nnht of Weevih Again, one hundred and forty-five tons of American maise were subjected to the same process, and at two siftiSs a ton of these andthre^uarten Beetles had of Weevils were removed. Now consumed sevpTal fim ■+ ^ each corn before it attained the nerfect ISte T.i °™

of some two tons of corn, instead of all owing it to be eltn bv ttonTtbc H ''>'<>“ “«-*od in urtpor! uon to the diminution of the storp? Tf 4.1, P^opor-

-“ZydXr “ ‘teyso;

mside has two recmvld^rook^T/^^^^^^^ enTof the bod'''''^

the grain throughout its larval and pup^ Hfe.

There has been some controversy among systematic entomologists with regard to the insects which come next in order. Some, thinking that they ought to form a separate group, have given them the name of Xylophagi, i.e. ^ timber-eaters ; while others have contended that they are really Weevils, and ought to form the last family of that group. The weight of opinion seems to be on the latter side, and we will therefore take some examples of the family of Weevils, called Hylesinidae, i.e. ‘ wood-devourers.’ The name is a very appropriate one, as we shall presently see.

In this family of Weevils the head has but a very short beak, in shape and deeply sunk in the thorax. The and is globular are elbowed, and have along basal joint and a flattened antennse front tibiae are broad at the tip, and used for digclub. The and the mandibles are short, strong, sharp, and

ging purposes, They are all timber-feeders, and sometimes work triangular. in the forests, even when the trees are still terrible destruction living.

Our first example of this insect is called Fi/Zesmws crenatus, on Woodcut XX. Fig. 1. This genus may and is represented the long oval club of the antennse, and the slight be known by The colour of this insect is black, the spurs of the tibiae. boldly punctured. The elytra are Pj^^chythorax is thickly and striated and ‘ crenated,’ i.e. covered with black, and are both of circles. From this pecuUanty, the insect marks like parts title, <yrenatus. The interstices between lias derived its specific The body is covered with down, and the striae are wrinkled. This is not a very common insect, but may rather elongated. of old trees. Four species of this be found under the bark genus inhabit England.

XX. Fig. 2, is shown the most destructive

On Woodcut that we have in this country. wood-eating Beetle name it is, the and a very appropriate Scolytv^ destrMt<yr, origin, and refemng to the name being of Greek

geJrio makes when in the larval or burrows which it

L passages itaelf. There me s«

state! and the specific name explaining example serves a Scolyti, but the present

species of British This genus is disting

the best type of the whole genus.

by the shape of its body, which is obliquely cut off behind, and

by the club of the antennse, which is three-jointed, solid, and

flattened. The last joint but one of the tarsus is cleft.

The colour' of our species is slightly variable, but is mostly

as follows : — The head is black, wrinkled longitudinally, and

the thorax is very large in proportion to the size of the insect,

^ Hylrainus crenatug. Prionus coriarius. 4. Tc Scolytus destructor, c. ^eraph.cus. 5. CaUidium yiolaoeum. a Prionus, lai-va. b. Tomicus,

Scolytus, larva.

and is covered with very small punctures. The elvtra are vetoes black, sometimes pitchy, and sometimes blrt! between the strta hfiug punched sr punctured. So much for the Will now appearance of this Beetle-w! proceed to its history.

die'! to "“’“r deposit her eggs, she ZndT r for a favourable »P«t. Having Havtog found it, she sets to work and gnaws a hole

completely through the bark, until she gets between the bark I and the solid wood. She next drives a tunnel, scarcely wider I than her own body, and then goes back along the tunnel, and I deposits her eggs along it. In many cases she exhausts all her I life-powers in the effort, and dies before she can entirely escape I from the burrow, the entrance of which is stopped up by her I body, so that no foe can enter. i

The eggs are soon hatched, and then the larvae begin their I destructive work. They feed on the soft inner bark, and each I as it feeds, instinctively turns itself at right angles to the I larva, burrow in which it was hatched, and gnaws for itself a tunnel, I which widens in proportion to the growth of the larva. These I burrows extend for an inch and a half or two inches in length, I

the result is, that a piece of bark, some three inches or I and is completely severed from the tree and can I more in diameter, its office. At the widened end of the burrow I no longer perform the larvEe assume the pupal form, and, after undergoing their I into the perfect insect, gnaw their way through the I change bark, and are ready to lay the foundations of new colonies. I a great number of these insects bore into a tree, they I

When it entirely, the bark being separated as com- I often destroy from the wood as turf is severed from the ground when I pletely under it. There is a tree — or rather, what I the spade is passed within a few yards of my house, which I was a tree — standing Scolytus. The whole of the bark has has been killed by the nothing is left but the naked wood, scored all peeled off, and over with the radiating tunnels of the destroying insect. ^ j

Should the reader wish to examine this insect for himself, | in so doing. He has only to visit any he will find no difficulty grow, and he is nearly sure to find the j place where elm-trees is perhaps the best time for - Scolytus under the bark. August insects, the krvae, and the i the purpose, as then the perfect The larva is white, thick, and fleshy, , pupae can be discovered. probably to aid the creature m the back is deeply wrinkled— the wood, this being an absolute conforcing its way through , cannot remain in the same place, dition of existence. It it grows so fast that the unyielding^ substances around

because increase in size, and it would in

would not permit its therefore, to push iteelt > soon perish. It is forced,

quence the space which was ongiua y

onwards, and to occupy

by the wood and bark on which it has fed, and for this purpose the bold wrinklings of the upper surface afford as useful means of progression to the insect as the ventral scales of the snake do to the reptile. The head is hard and scaly, and the jaws are exceedingly powerful. One of these larvae is shown on Woodcut XX. Fig. c.

When nearly full-fed, the greater number of the larvae burrow directly into the tree, making holes about half an inch in depth, at the bottom of which they are quite safe, even though the bark should fall off, as is often the case. They are, further, protected from weather and the eyes of hungry birds by the ‘ frass,’ or digested remains of the wood, which fills up the tunnel behind the larva. It is much doubted whether the Scolytus ever attacks a healthy tree, principally, as is conjectured, because in such trees the burrows of the insects are filled with sap, which not only drives out the Beetles, but prevents their eggs from being hatched. Still, when a tree becomes unhealthy, the attacks of the Scolytus prevent it from recovering itself ; and such serious damage has been done by this insect to our trees, especially the elms in and about London, that the attention of entomologists has long been directed to the subject, in hopes of discovering some device by which the ravages of the Scolytus may be checked, if not altogether stopped. As yet, however, no scheme has succeeded. Various plans have been suggested, such as injecting poisonous fluids into the hole made by the mother Scolytus. This might possibly answer, provided the operator could be sure of discovering all the holes, and provided that the liquid did not kill the tree as well as the insect. The ‘ Grishurst Compound ’ would do as much in this way as anything could, but it cannot be employed on a large scale.

At present, the opinion seems to be that the only plan which offers the least probability of success is a ‘ stamping out ’ process, similar to that which saved us in the time of the cattleplague. By this plan, all trees which are visibly attacked by the Scolytus are to be cut down, and stripped of their bark and the outer layer of wood, which are then to be burned, so as to destroy the Scolytus, its larvae, pupae, and eggs.

I)r. Chapman states that all the species of Scolytus are in the habit of fighting with each other. They ‘ have a fashion of

placing their foreheads against other individuals, and giving a I thrust by pushing forward the jaws. They employ this process ■ to remove another Beetle from a station which they desire to I occupy ; it appears also to be an expression of anger, sometimes ■ two Beetles having an encounter in this way ; and they use the ■

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