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parts aborted, and consequently take no nourishment as perfect insects, their life being 

 •correspondingly brief. This spiral tongue consists of the elongated soldered maxilla? ; 

 the mandibles or jaws of the larva becoming rudimentary in the perfect state. The sub-equal 

 wings consist of a membrane traversed by a simple system of nerves or veins, the neuration, 

 covered with scales and fringed with hair. The thorax has a distinct portion in front, 

 the collar (collare). The abdomen usually tapers posteriorly, in some females it appears 

 blunt, being provided with heavy tufts, the hairs from which are used sometimes as a 

 nesting for the eggs. As caterpillars, the Lepidoptera usually feed and grow, whereas as 

 butterflies and moths they occupy their brief lives chiefly in propagating their kind, the 

 sexes being separate and the females laying eggs, singly or in patches or clusters, from 

 which again caterpillars emerge. To this latter there are a few exceptions. In the case 

 of some Spinners and the Tineid genus Sohnobia, a parthenogetic race has been observed, 

 the virgin females laying eggs which produce only females, no males being hatched, the 

 -complete species is only produced by a union of the sexes. What are called " Herm- 

 aphrodites " are also sometimes found, in which, in one and the same individual, the two 

 sexes are variably united, one side being more or less completely male, the other female. 

 This is seen occasionally in the larger spinners, Platysamia Cecropia and Callosamia 

 Promethea, when the division is clearly marked by the sexual differences in the antennae 

 and colour. Such specimens are abnormal productions and infertile, not true Herm- 

 aphrodites as the snails normally are. Bastards, resulting from the union of two species, 

 occur, and have been noticed, especially in the hawk moths, but I have never seen an 

 undoubted example of this kind myself. By confining the perfect insects, bastards have 

 been artificially produced ; in nature they seem to occur rarely. New species are 

 probably never formed in this way of unnatural selection. 



The three divisions of the lepidopterous body mark also a division of function. The 

 head is provided with jointed appendages for the purpose of holding, biting and masti- 

 cating the food, or sucking the same in the perfect state, and here the sense-organs, eyes, 

 ocelli and antenna? are situated. The three-ringed thorax supports three pairs of slender 

 legs and the wings — the organs of locomotion. The nine-ringed abdomen contains the 

 digestive and reproductive parts ; breathing or the aeration of the blood is accomplished 

 by stigmata opening on the sides of the body, chiefly the abdomen. In the butterflies 

 those forms are highest in rank in which the front pair of legs are useless for walking, 

 being apparently taken out of the locomotive series, curiously shortened and elevated, 

 and seem like an additional pair of palpi or head organs. The interesting details of the 

 anatomy of the head by my kind friend, Mr. Edward Burgess, should be known by 

 students. 



For the essential characters separating the butterflies and moths, I refer more par- 

 ticularly to a paper of mine read before the American Association for the Advancement 

 of Science in August, 1873, the gist of which I here reproduce with fuller statements. 

 There is first to be noted the differences in the structure of the antenna?. These usually 

 long, jointed, thread-like organs, situated on each side of the vertex, are quite uniform in 

 shape throughout the butterflies, being more or less club-shaped or thickened at the tips. 

 From this latter character the name Rhopalocera has been given to them by Dr. Boisduval. 

 On the other hand, the moths have the antenna? of quite various shapes and length, usually 

 showing some sexual difference in structure. The position of these organs in the two 

 divisions exhibits a marked change. In the butterflies the antenna? are comparatively 

 rigid and straight, and are directed upwards and forwards. In the moths the antenna? are 

 flexible and held horizontally, being not unfrequently deflexed along the sides of the body 

 in repose. The antenna? are apparently less used by the butterflies, which depend more 

 on their sight during their diurnal activity. That they are the organs of smell and are 

 probably also sensitive to vibrations of the air, has been suggested by experiments. The 

 feathered antenna? of so many male moths seem to be sensitive to odours given out by the 

 female. In this way the fact is accounted for, that male moths will come long distances to 

 find unerringly specimens of the opposite sex. One needs only to expose a freshly- 

 hatched female of our larger spinners, even in the heart of the city, to verify this state- 

 ment. The moths, resting in the daytime, seem also to depend on their antenna? to warn 



