Another species (_Tabanus bovinus_) is twelve lines in length, and of a blackish brown. The palpi, the face, and the forehead are yellow; the antennæ black, with a whitish base; the thorax, covered with yellow hair, is striped with black; the posterior edge of the segments of the abdomen pale yellow; the legs yellowish, with the extremities black, and the exterior edge of the wings yellow. This species is frequently met with in woods. A third species, _Chrysops cæcutiens_ (Fig. 34), which belongs to the same family, and of which the generic name _Chrysops_ signifies golden-eyed, torments horses and cattle very much by biting them round the eyes. Its thorax is of a yellowish colour, striped or spotted with black; the abdomen yellow, and the eyes golden. In the next group of the Brachycera the sucker is composed of four bristles, and the antennæ generally terminate in a point which appears to be rather a development than an appendage. This group includes a number of genera, but the following only possess sufficient interest to claim our attention. From the _Tanystomæ_ we select the families of the _Asilidæ_, _Empidæ_, and _Bombylidæ_. As types of the _Brachystomæ_ we select the _Leptidæ_ and _Syrphidæ_. [Illustration: Fig. 33.--Tabanus autumnalis.] [Illustration: Fig. 34.--Chrysops cæcutiens.] The chief characteristic of the _Asilidæ_ is strength. All their organs combine to produce this quality, which they display only too much, being as formidable to cattle as the _Tabani_, but even surpassing those insects in natural cruelty. The _Asilidæ_ unceasingly attack other insects, and even those of their own kind. Their trunk is strong; one of the fibres of the sucker is furnished with small points, turned back, which are intended to hold firmly to the body into which it has entered. They carry on their devastations in the glades of woods and on sunny roads. We will mention in this group _Asilus crabroniformis_ (Fig. 35), an insect ten to twelve lines long, having a yellow head, black antennæ, and thorax of a brownish yellow. The three first segments of the abdomen are black, the second and third having a white spot on each side, the remaining segments are yellow. The wings are yellowish, spotted with black on the inner and hind margin. This species is common over the whole of Europe, and lives at the expense of caterpillars and other insects, of which it sucks the blood with the greatest voracity. [Illustration: Fig. 35.--Asilus crabroniformis.] [Illustration: Fig. 36.--Bombylius major.] The _Empidæ_ live in the same way as the _Asilidæ_, but the males are chiefly nourished by the juices of flowers.