INTRODUCTION. xv 



and ridged like a saw. At its extremity is the tip, the apex, 

 or the anterior angle of the wing. This is often more or less 

 angulated, sometimes being pointed, or running out into a 

 projecting angle, or it may even be hooked ; but in many 

 species it is rounded off. The longest portion of the wing is 

 generally at or a little below the tip. The edge of the wing 

 furthest from the body is called the hind-margin. Sometimes 

 it is regularly rounded, in which case the wings are said to be 

 entire, or it may be more or less toothed (dentated, or denticu- 

 lated), or obliquely hollowed between the ends of each two of the 

 nervures (sinuated). The concave spaces between the nervures 

 are then called "incisions." On the fore-wings, the hind-margin 

 is generally slightly curved towards the hinder angle (the anal 

 angle as it is sometimes called, though this term is properly 

 applied only to that of the hind-wings), but it is frequently 

 nearly straight, or more or less convex or concave, or with 

 angular projections ; in fact, its outline varies more in different 

 species than that of any other part of the wing. On the hind- 

 wings, the hind-margin is generally rounded, but is sometimes 

 angulated once or twice, or furnished with a more or less long 

 projection, called a tail, most frequently at the end of the 

 upper median nervule (see below), though tails may be thrown 

 off at any of the lower nervules, either independently or con- 

 jointly with one at the point just mentioned. When the hind- 

 wing is simply angulated we have called this point the " outer 

 angle." The anal angle of the hind-wings is often rounded off, 

 or even concave, but sometimes projects into a point, or even a 

 tail. The inner-margin is opposite to the costa on the fore- 

 wings and is generally nearly straight, or very slightly concave, 

 but in some genera, especially in some of those allied to 

 Euplcea, it is strongly concave. On the hind-wings the 

 inner-margin lies parallel to the sides of the abdomen, and 

 sometimes forms a kind of gutter to receive it, or is concave. 



