THE IDEXTIFICATlOy OF IXDIAX BUTTERFLIES. 
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completely coalesced or what is called anastomosed. In one group the basal 
portion of vl2, often also of the sev and oven of the mv is swollen. 
In the hindwing (H or H\V) there are only 8 veins, but via is present in the 
majority of species, as is also the short curved .spur near the base of v8, known 
as the precosta! vehi (pcv). In some species there is a small precostal cell formed 
either by a small vein between v8 and the sev or v8 and the pcv. Normally 
all the veins from 2 to 8 spring from the cell, but sometimes vs 3 and 4 may be 
forked bej’ond the cell. The middle and lower devs as well as vo may be absent 
or only faintly indicated. 
The secondary sexual characters often cause curious distortions or swellings 
of the veins. 
In the older text books vl is called the submedian, vs 2, 3 and 4 the first, 
second and third medians ; vs 5 and 6 F and vo H the discoidal veins, v5 also 
being knovTi as the radial ; vs 7 to 11 F and 6, 7 H the subcostals ; vl2 F and 
v8 H the costal. The dev is sometirnes called the transverse vein. 
Differences of venation are of variable value in different groups ; sometimes a 
diffei'ence will separate whole sub-families, while sometimes well marked 
differences are to be found between the sexes of the same species. As a rule 
the differences observable on the forewing are more important than those of 
the hindwing. 
11. The shape of the wings is often an important consideration, though 
here again the value of the feature is variable ; sometimes the seasonal and sexual 
differences are remarkable. The presence or absence of one or more tails (cau- 
date) towards the tornus of the hindwing is usually important, though there 
are species, which may or may not have a tail. The tails may be very fine 
(filiform) or stout and fringed like the rest of the wing (ciliate). The costa may 
be straight or more or less highly arched and sometimes on the fore wing it is ser- 
rate or furnished with teeth like a saw, easily felt by drawing the tip of the 
finger along it from the tip towards the base ; on the hind wing the costa is 
occasionally concave. The apex may be rounded, sharply pointed or produced 
in comparison with the rest of the wing ; occasionally it is produced and the 
termen is concave below, when it is termed falcate. The termen or outer mar- 
gin may be sinuate or wavy, straight, convex or somewhat rarely concave ; 
crenulate or dentate, when produced at the end of each vein and concave between 
the veins. The dorsum may be straight or concave ; sometimes in the males 
it is highly convex. The tomus of the hindwing is often more or less produced, 
but more usually it is rounded ; it may be angled sharply ; sometimes, espe- 
cially in the blues, it is furnished with a more or less prominent lobe. 
12. The cilia are the fringes, composed of two or three layers of scales that 
are to be found bordering the termens of the wings. They may be cinereous 
(ashy), white, yellow or brown ; or they may be more or less chequered. Their 
length is variable and often more pronounced at the tornus of the hind wing, 
where also they may be differently coloured. 
13. The differences between the markings on the wings are used to separate 
species, but here again a word of caution is necessary ; the seasonal or sexual 
differences are often most extraordinary ; development under identical condi- 
tons often causes the species of widely separated genera or even families to 
look alike and an examination of the structure is necessary. In some genera the 
species are so alike that they can only be separated by an examination of the 
genitalia or of the secondary sexual characters. The variation between the 
individuals of the same species is often considerable and there is a tendency to 
the obsolescence of the markings, while so-called sports or mutations are occa- 
sionally to be met with. There are quite a number of skippers belonging to 
different genera which are plain brown insects bearing no markings whatsoever. 
A few technical terms are used when describing a butterfly, which the beginner 
should master. 
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