BUGS. 



295 



moved with a degree of rapidity not usual to such insects, at least to the family Pedi- 

 culida?. In many species a very great difference in color and markings is observable 

 after each moult, so much so, that unless an opportunity of examining a series of all 

 sizes and ages occurs, the identity of the species would scarcely be conjectured." 



Two principal families include most of the species belonging to this group. The 

 first, PHILOPTERID-E, may be distinguished by the persistent absence of cushions from 

 the tips of the two-jointed, or in a few cases one-jointed tarsi, and by the filiform 

 antenna?, which are composed of either five or three joints. 



In the genus Pkilopterus (which has been divided into nine sub-genera by Piaget, 

 based chiefly upon differences in the form of the head), we observe small insects of 

 extremely varied patterns. Many of these are provided with curious attachments to 

 the sides and angles of the head, and all have five-jointed antenna?, tarsi with two 

 claws, and live between the feathers on the necks and under the wings of birds. 



A striking example of this genus is the P. (Goniocotes} hologaster. It is pale 

 yellow, with the margins of the broadly rounded clypeus, sides of the head and 

 band at its base, front margin of the mesothorax (excepting the middle), the outer 



FIG. 341. Trichodtctcs caprce. FIG. 342. Goniocotes burnettii. FIG. 343. Trichodectes subrostralus. 



edge of the femora and tibia?, and the borders of gray patches on the sides of the 

 abdominal rings deep black. The head forms a broad shield deeply cut out behind 

 the antenna?, and again at base. A fringe of long, remote bristles also passes around 

 the whole outer margin of the body, and a few shorter bristles are set upon the legs. 

 It is one of the larger species, measuring about one-tenth of an inch in length ; and is 

 common upon the domestic fowl in Europe. This is closely related to, if not identi- 

 cal with, the form frequently found upon hens in the middle States. Dr. Packard 

 describes an allied species, with the name G. burnettii, which he has found upon the 

 same fowl in New England. It differs from the preceding in having the sides of the 

 head nearly entire, the clypeus longer, ovately rounded, the antenna? stouter, and with 

 the second joint shorter, and the abdomen relatively narrower. 



Perhaps the most remarkable forms belonging here are those which infest the 

 turkey and the peacock, Goniodes stylifer and G.falcicornis. The latter has attracted 

 the attention of many observers, and because of its singular appearance has been fig- 

 ured in numerous text-books of natural history. It is of a bright chestnut yellow color, 

 with wide lateral bands of liver-brown. The head is broad, with angular blunt lobes 

 behind, marked with brown, the widely rounded clypeus is sinuated each side, and in 

 the cavities thus formed the stout antenna? are placed. These latter organs are hooked 



