If the reader should be disposed to prepare a portion of the compound eye for the microscope, he will find that the operation, though a rather tedious one, will well repay him for the tiouble. Should he wish to do so, he can so arrange the eye that some small object can be seen through it, when the effect will be extraordinary, the object being apparently multiplied in accordance with the number of facets in the field of the microscope. The result is, in fact, exactly the same as that which is produced by looking at any object through an ordinary multiplying glass. It is not, however, to be imagined that because the compound eye of the insect has so many facets, the insect perceives the object multiplied in proportion to the facets ; for, although the numerous facets give the insect an extended range of vision, they convey but one image to the brain, just as the duplicate eyes and ears of man convey to the mind but one image and one sound.

In addition to these compound eyes, many insects possess several small simple eyes, called ocelli. They are very small, and in the Beetles are two in number, and placed on the back of the head. They can be very easily seen in some of the Hymenoptera, such as the bees and wasps. The eyes of the spider are of a similar character.

Having examined the head, we now take the next division of

the insect, namely the thorax. This important part bears all the instruments of locomotion, whether they be legs or wings ; and is most wonderfully constructed for the pm’pose, being supplied in the interior with hard projections that are needed for supporting the powerful muscular apparatus needful for flight, and the less powerful, but still important system by which the legs are moved.

The thorax is internally divided into three parts, which we call prothorax, or front thorax ; mesothorax, or middle thorax ; and metathorax, or hinder thorax. Beginning with the prothorax, we find it again divided into two portions, the upper and the lower — the former going by the name of pronotum, i.e. in front of the back, and the other called prosternum, i.e. in front of the breast. Fig. 7 shows the pronotum of the Stag Beetle : 7aa are the lateral margins, 76 is the anterior margin, 7cc are the posterior angles. Id the posterior margin, and lee the anterior angles.

Next we come to the prosternum, which is shown at Fig. 8 ; 8a being the sternum, and 866 the insertion of the coxa, a joint which will be presently described.

The mesothorax with the abdomen is shown at Figs. 9 and 10, the former exhibiting the upper, and the latter the under surface. In the last figure, a is the metasternum, 6 the abdomen, c the parapleura, or side-pieces (sometimes called paraptera, because they are situated by the wings), and d the episterna, or breast-pieces.

Each of these portions is set apart for a definite use, and is employed for the attachment of some portion of the locomotive apparatus.

The prosternum is used to carry the front pair of legs, as can be seen by looking at the under side of any large Beetle, or indeed of any small one, by the aid of a magnifier.

Ihe mesothorax bears the elytra, or wing cases, and the intermediate pair of legs, the former being attached to the upper part, or mesonotum, and the latter to the lower part, or mesosternum. The reader must remember that the word ‘sternum’ always signifies the breast, or under side of the thorax, and ‘notum’ the back, or upper side. Lastly, the mesothorax bears the lower, or membranous, wings and the last pair of legs. As before, the wings are attached to the

inetasternum. dipper part, or metanotum, and the legs to the lower part, or

We come now to the legs, the three pairs of which are represented successively at Figs. 11, 13, 15; the first pair being called the anterior legs, the second the intermediate legs, and the third the posterior legs.

These legs are divided into several portions, which are marked at Fig. 11. Beginning at the extremity of the limb, a is the tarsus, or foot, which consists of several joints. There are mostly five joints in the tarsus of Beetles, but in many families one or two of the joints are so small as scarcely to be visible, and only to be detected by a practised eye with the aid of a lens. Next comes the tibia, or shank, which is shown at h. Then follows the femur, or thigh, as seen at c. This is attached to a small joint called the trochanter, which is drawn at d ; and last comes the coxa, or the joint which connects the limb with the thorax. The action of the coxa IS very curious, it being a kind of ball-and-socket joint, but with a limited range of movement, so that the legs cannot be spread too far. The same divisions of the joints are found in the three sets of legs.

We next come to the wings. The upper pair, or elytra, are shown at Fig. 14. For convenience of description they are marked into several divisions. Fig. 14a is the suture, or line of junction between the two elytra. The apex is shown at c, and the base at d. The middle, or disc, is marked e, and the lateral margin is at h. Fig. 17 shows one of the wings expanded, as if for flight; Fig. 18 is the opposite wing, represented as folded, and at Fig. 16 are shown both wings as they appear when the elytra are removed.

At first sight some of these terms may appear to be harsh, repulsive, and difficult to master. In reality they are not so, and a knowledge of them is absolutely necessary to anyone who wishes to understand the description of an insect, and himself to describe insects intelligibly. They form a kind of shorthand by which knowledge can be rapidly communicated, and the trouble taken in learning them is amply repaid by the advantage gained by the student, even were the trouble multiplied tenfold.

But, in reality, there is scarcely any trouble needed. If the

entomologist should content himself with merely intending learning a string of names by rote, he must expect to find his lesson a hard and repulsive one, and that it will he forgotten almost as soon as learned. Practical knowledge is ever the best, and the reader who intends to become an entomologist should take some Beetle — the largest he can find — and compare it, piece by piece, with the figures and description.

The most effective plan of all, however, is to take the Beetle entirely to pieces, and to lay out the portions on a card in their proper order, numbering each piece, and writing an index to the numbers. The various portions can be fixed to the card by diamond cement or Kay’s coaguline, the latter having the advantage of great holding power, so that a very little is required, perfect transparency, and sufficient elasticity to guard against the tendency to chip away from the object, which is so unpleasant in ordinary gum. I recommend takingtwo Beetles, so as to show the upper and under sides of each portion. This will be found peculiarly interesting in the thorax.

Before any attempt at dissecting the Beetle it should be steeped in soft water for a time, until the soft parts are thoroughly dissolved. The water should then be poured away, and fresh water substituted until the whole of the muscles and viscera have been washed away. Care must be taken lest any of the smaller joints be lost during this process. When the whole skeleton is fairly laid out, it can be mounted in a glass frame, and, besides serving as an infallible guide to the external anatomy of the Beetle, it is really a pretty and ornamental object. Many years ago, when I first began the study of entomology, I thus prepared several Beetles, and the knowledge thus gained has never been lost. Had I studied books alone, I should not have been able to gain the information half so easily, or to have retained it half as long.

CHAPTER II.

the GEODEPHAGA.

.The word with which this chapter is headed is not a veryalluring one, and yet to an entomologist it would say that the chapter contains the history of the best developed and some of the most interesting of the British Beetles. The term Greodephaga is formed from two Grreek words, signifying earth-devourers, and is given to the large group of predacious Beetles which live on the ground. There is another large group, called the Hydradephaga, or water-devourers, i.e. those predacious Beetles which inhabit the water. We will take these two important groups in succession, selecting such examples as may best illustrate them.

It must be, in the first place, observed that any Beetle may be recognised as belonging to either of these great groups by the structure of the mouth. In reference to the illustrations already described, the reader will see that each of the maxill® 4) is furnished -with a four-jointed maxillary palpus. All these carnivorous Beetles possess the same organs, but, in addition, they have an inner lobe, which is also furnished with its palpus. Several examples of this structure may be seen by reference to the accompanying illustration (Figs, a, c, e, and /). Both these groups are associated in one large group called Adephaga, the word being a Grreek one, and signifying greedy or gluttonous.

Beginninh -with the Geodephaga, we take the first family of the group, the Cicindelid®, or Tiger Beetles. In all these Beetles there is a little movable hook at the end of the maxillae, and the ligula is very short, and not appearing beyond the mentum. There is only one genus of these Beetles inhabiting England, and this is the typical genus Cicindela. The

of this genus vary but little in size, being about half members an inch in length, having slender legs and antennae, powerful and curved jaws, and very rounded and prominent eyes. They are all prettily coloured, and some are absolutely magnificent when viewed with the aid of a magnifying glass.

Never was a popular name more appropriate than the title of Tiger Beetles, which has been given to this genus. If we

Coleoptera.

Dromius qiiadrimaculatuB. 2. Lebia cyanocephala. 3. Tarns axillaris. 4. Clivina lessor. 5. NotiopMIus biguttotus. a. Dromius, maxilla. b. Cioindela, head. c. Cicindela, maxillary palpus. d. Tarus, labial palpi. e. Notiophilus, maxillary palpi. /. Lebia, maxillary palpi. can imagine tigers who, in addition to active limbs, their teeth, and their talons, are furnished with large and powerful wings, we can form some idea of the part which these creatures play in the world of insects.

We will take as our first and typical example the common Green Tiger Beetle or Sparkler {Cicindela campestris).

At Fig. h of Woodcut II. is shown the head of this insect,

magnified some six diameters, in order to show the extremely

formidable jaws with which it is armed. These jaws are not

only sharp at their points, and strongly 'curved, but are

toothed ; so that when the Beetle has once boldly seized its prey, the

unfortunate insect has but little chance of escape.

The colour of this beautiful beetle is gold-green above, and

shining copper-green below ; and there are several yellowish spots on the elytra, varying much in shape, number, and hue. Sometimes there are only three, but in many specimens there are six. In former times, the variety in the number of spots was thought to indicate that the Beetles belonged to different species, but it is now decisively ascertained that they are only varieties of one single species.

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