16 COLEOPTEEA OF INDIANA. 



are miieh shorter, leavinp- several seiiments of the abdomen exposed. 

 Almost always they fit elosely together in a straight line along the 

 middle, this line of jnnction being called the suture. Rarely they 

 are somewhat separated near the tips, when they are said to be 

 deJiiscent. Their onler front angle or shoulder is known as the 

 humerus (plural Jninicri). As in the thorax, the sides of the elytra 

 are often separated from the upper portion or disk by an acute 

 margin, beneath which a portion of each elytron is inflexed. Lying 

 next to the edge or margin is a piece of varying width and some- 

 times extending from base to apex known as the cpipleura. The en- 

 tire inflexed portion is often, but wrongly, called the epipleura. 



The tips or apices of the elytra vary greatly in shape, sometimes 

 being truncate, more often rounded and rarely ending in sharp 

 points or even spines. Oftentimes the side margins are more or 

 less deeply sinuate near the tips. 



The sculpture of the elytra is nnu'li used in classification. Very 

 often the disk is marked with longitudinal impressed lines or fine 

 narrow grooves called striee. An elytron so marked is said to be 

 striate. The space between any two of these strit^ is termed an 

 interval. When the stria' are fine and shallow, the intervals are 

 usually flat or nearly so ; wiien deep and rather wide, the intervals 

 are more or less convex. Very often the striie are punctate, i. e., 

 marked by rows of pu)iefures or impressed dots. The intervals are 

 also often punctate or punctulate, the latter term meaning that the 

 punctures are very fine. When the punctures are absent from 

 stria? or intervals they are said to be sniootli or inipunetate. When 

 the punctures are not in rows luit scattered here and there over the 

 surface of the elytron they are termed irregular or confused. 



In addition to the ordinary punctures above noted, or often 

 when the elytron is otherwise smooth there may be present one or 

 m(u*e larger impressions called dorsal punctures. These are usually 

 somewhere between the suture and the third stria, though they may 

 be anywhere on the disk. Quite often the entire npper surface of 

 the elytra (as well as that of either or both the head and the thorax) 

 may be seen under a lens to be very finely reticulated or covered 

 with minute cracks like the human skin. The surface is then said 

 to be edutaeeous. When densely alutaceous the surface is generally 

 more or less opaque. In addition to the forms of sculpture above 

 mentioned the elytra may be granulate, or covered with many mi- 

 nute elevations ; tuberculate, or with fewer and lai-ger elevations. 

 They may also ])e pitted, foveate or impressed in many ways. In 

 addition to the sculpture they, as well as other parts of the body. 



