74 DR. HARRIS'S REPORT. April, 



above. The head is broad, the thorax short, transverse, and as 

 broad as the elytra ; the antennae are ten-jointed, the first joint being 

 . very long, and the four last projecting at the sides like the teeth of a 

 comb. But the mandibles, or upper jaws, of great size, extending 

 like the horns of cattle, or branched like those of the stag, forn) the 

 most conspicuous character. These insects fly abroad during the 

 night, and frequently enter houses. They are vulgarly called horn- 

 bugs, and are dreaded for their formidable aspect, but are perfectly- 

 harmless. The larvas are common in all decaying trees, and are 

 frequently found in the trunks of apple-trees. 



The preceding insects have five joints to all their feet. There 

 are others which injure vegetation, and which have only four joints 

 to the posterior pair of feet. 



In Tenehrio^ the body is elongated, hard, flattened, and entirely 

 covered above; the antennae are moniliform, or composed of grains 

 like the beads of a necklace, and gradually enlarge towards the tips; 

 the thorax is square ; the elytra are not united at their junction ; and 

 the legs are curved. The larva is long, slender, nearly cylindrical, 

 very smooth, and of a pale rust or dirty yellow color. The first 

 segment behind the head is larger than either of the others ; this, as 

 well as each of the two following segments, is furnished beneath with 

 one pair of legs ; the tail is acuminated, the tip in some species fur- 

 nished with two minute vertical spines ; under the tail, at the junc- 

 tion of the two last segments, is a membranous space in which is 

 concealed a retractile fleshy tubercle, from which issue, when the 

 animal walks, two horny movable parts which ])erforni the office of 

 legs. The larva state continues during two or more years. The 

 perfect insects are nocturnal, as the name indicates. 



Tencbrio granarius. The larva lives in stables and granaries, 

 subsisting upon corn and meal. It has considerable resemblance to 

 that of the small species of Elater. The pupa is found in .lune in 

 places inhabited by the larva. The perfect insect is developed about 

 the middle of June. 



A remarkable case of the introduction of this insect into the hu- 

 man body is recorded by the late Dr. Coffin of Boston, exhibiting 

 a great change in the ordinary habits of the insect, showing the ne- 

 cessity of great attention to cleanliness in cases of sickness, and fur- 



