PULEX. INSECTS. 249 



Sucks the blood of man, the dog, and the cat Its larva inhabits dung, under 

 the nails of uncleanly persons, in the nests of birds, above all the pigeon, attaching 

 itself to the necks of the young. 



P. penetrans, Lin. The Chigger. Beak as long as the body 

 Shaw, vi. 459. 



This insect is known in America under the name of Cinque. It introduces itself 

 under the nails of the feet, and under the skin of the heel, and soon acquires consi- 

 derable size from the increasing bulk of the ova, which it carries in a membranous 

 sac under the belly. The numerous family to which it gives birth occasions by 

 remaining in the wound a malignant ulcer, difficult to cure, and sometimes proving 

 fatal. If due care, however, be taken to wash the feet often, and above all rub them 

 with bruised leaves of tobacco, or other acrid and bitter plants, there is little chance 

 of material inconvenience. The Negroes extract the animal with address. 



ORDER IV. COLEOPTERA, lum.Eleutherata, Fab. 



Four wings, of which the two upper ones are in the form of cases; 

 mandibles and jaws for mastication ; under wings folded 

 across ; elytra crustaceous, and the suture straight. 



The Coleopterous insects are of all others the most numerous and best known. 

 Their singular forms, and the brilliancy of the colours of many, have attracted parti- 

 cular attention, while the hardness of their teguments renders their preservation easy. 

 The animals of this order have always two antennas, composed generally of eleven 

 joints ; two eyes in facets ; a mouth formed of a labrum, two horny mandibles, and 

 two jaws, bearing each one or two palpi, and a lip of two pieces, of which the lower and 

 more solid portion is called the chin (mentumj) and the upper, often membranous, is 

 termed the Idbium. This is furnished with two palpi, called the labial palpi. The 

 maxillary palpi are to the number of two or four, and when of this last number, the 

 interior ones have never more than two joints, and the exterior four. The forms 

 and the proportions of these organs vary much, according to the genera. All the 

 Coleoptera are destitute of ocelli. The trunk is divided into two parts. The anterior 

 portion large, solid, and, bearing the first pair of feet, is generally termed the thorax ; 

 the second, intimately united to the abdomen, serves as a support to this portion of 

 the body and the other organs of movement. A triangular crustaceous plate, more 

 or less projecting between the elytra, at their anterior termination, is termed the scu- 

 tellum ; the under part of the body between the legs is the sternum. The elytra or 

 wing-cases and the wings rise from the lateral and upper margins of the hind part of 

 the thorax or back. These elytra are crustaceous, and in repose join in a right line 

 along their internal margin or the suture, and always on a horizontal plane. They 

 generally conceal the wings, which are broad and plicated transversely. The abdo- 

 men is sessile, or united to the thorax in all its breadth, and covered by the ely- 

 tra and wings. The feet, six in number, are composed of four principal pieces, the 

 hip, the thigh, the leg, and the toe or tarsus. The number of joints in the tarsi vary 

 from one to five, and the last is terminated by two hooks. Coleopterous insects un- 

 dergo a complete transformation. The larvae resemble a small worm, with a scaly 

 head, a mouth analogous by the number and functions of its parts to the perfect in- 

 sect, and commonly six feet. The Romans used the larvae of one species as food. 

 The Coleoptera are very generally distributed over the world. Latreille divides this 

 large order into five sections, according to the number of the joints of the tarsi. 



SECTION I. PENTAMERA. 

 With five joints in all the tarsi. 



FAMILY I ADEPHAGI, Lat. 



With two palpi at each jaw, or six in all ; antennae almost al- 

 ways in the form of a filament or bristle, and simple. 



