INTKODUCTIOK 
13 
and the end of their trunk (as has been well shown by Mr. F. Darwin 
in the case of the Australian Ophideres fullonica, which penetrates even 
the rind of oranges) is bayonet-shaped and armed with saw-like teeth 
and ridges. 
The antennae of Lepidoptera have the characteristics of being well- 
developed and many -jointed throughout the Order, and in the great 
majority of genera long and conspicuous. The shortest antenna are 
found in the Moths known in England as Ghosts " and " Swifts " 
(family Hcpialidce)^ and the longest in the so-called " Long-Horns " 
among the smallest Moths (family Tincidce). Their form varies greatly, 
from the simple thread-like (filiform), or gently tapering {setiform), to 
the doubly comb-toothed (hipedinate) or feathered (plumose). Their 
office has not yet been certainly made out ; they do not appear to be 
employed as many insects of other Orders use them, viz., as feelers or 
organs of touch ; but, if they are the seats of any special sense, it seems 
probable, from the fact of their being, in very many cases, much more 
highly developed in the male sex, that they are olfactory.-^ The pro- 
minence of the antenna and the facility with which they can be 
examined, no less than the fact that their various forms are very 
characteristic in the main of certain large natural groups, have led to 
the employment of these organs as representative ones in separating 
and naming the divisions of the Order. Dumeril, in 1823, proposed 
four such divisions ; of which the first, Bopaloceres, comprised the Butter- 
flies or Clubbed-Horns, having the antennae knobbed or thickened at 
the tip ; the second, ClosterocereSj the Moths whose antennae are thickened 
about the middle (fusiform)^ included the Sphinges or Hawkmoths ; 
the third, Nematoceres^ or Thread-Horns, contained the Bombyces ; and 
the fourth, CMtoceres^ or Bristle-Horns, was composed of all the remain- 
ing Moths. The last of these divisions was a most heterogeneous 
assemblage, and neither it nor the two preceding divisions (which are 
comparatively natural ones) have been adopted by any lepidopterist ; 
but the first, Bhopalocera^ was accepted by Boisduval in 1836, and by 
Westwood in 1840. The former of these authors professed himself 
unable to separate the Sphinges from the other Moths as a primary 
division of the Order, and united all Dumeril's three groups into one, 
which he styled Heterocera^ or Varied-Horns ; and in this also he was 
followed by Westwood, who stated that he could not admit the minor 
divisions of the nocturnal Lepidoptera " to a rank equivalent to that of 
the whole of the Diurna." This simple partition of the Lepidoptera 
into the two great groups of those with clubs or terminal thickenings 
of the antennas, and those without them (however variable the organs 
^ It is noteworthy that the antennae are very highly developed in the males of those 
Bomhycidce which so readily discover the sedentary female under circumstances (such as 
enclosure in a shut box) which seem to preclude the employment by them of any but a sense 
of smell of extraordinary keenness. That this sense is the one exercised seems to be proved 
by the fact (to which I can testify in the case of Lasiocampa Quei'cus) that males are 
attracted by the empty box from which a female has been removed. 
