23 



NATURAL HISTORY. 



MOUTH OF THE PRIVET HAWK. 

 MOTH. 



a, Upper Lip- 6, Mandibles; r. Proboscis! 

 (I, Uudcr Lip ; e, Antenna;; /, Eyes. 



some Morphince, &c., seems to be fixed on the principle of a ball and socket joint. The scales 



consist of a double membrane, finely striated. Between the striae, and parallel with them, 



are arranged pigment cells ; but this is not the sole cause of their beautiful colours, for the edges. 



of the scales frequently refract the light, and thus produce the most brilliant metallic lustre. 



If the scales are rubbed off a colourless membrane remains, with branch- 

 ing nervures running through it. In this state it does not greatly differ 

 from the transparent wings of other insects, except for the sockets from 

 which the scales have been removed. 



Butterflies and Moths have six legs in the perfect state, but in some 

 families of Butterflies the front legs are rudimentaiy, and in the males 

 of a few Moths the hind legs are shorter than the others.* The tibiae 

 are not unfrequently furnished with spines in the middle or at the ex- 

 tremity. The tarsi are usually five-jointed, and generally terminate in a 

 pair of claws. 



Having noticed the legs and wings, it now becomes necessary to 

 describe the structure of the head and body, before proceeding to notice 

 the internal anatomy. As in all other insects, a fully-developed Moth 

 or Butterfly is composed of thirteen divisions, or segments, the first of 

 which forms the head, segments 2 4 foi-m the thorax, and the remainder 

 form the abdomen. The distinction between the thorax and abdomen 



is always well marked in the perfect insect, although it is not sharply indicated in the larva. 



The head is rounded, and generally rather broader than long. There are two large eyes on each 



side, formed of a great number of facets, and therefore called compound eyes. Their surface is 



covered with short hairs in 



some species, and is naked in 



others. In addition to these, 



there are sometimes two small 



simple eyes (often called stem- 



mata, or ocelli) situated on the 



vertex or top of the head ; but 



these are not present in many 



groups of Lepidoptera. The 



forehead is sometimes provided 



with a small horn or crest. 



Ths antennse are placed in two 



small hollows near the eyes, 



and appear to be organs of 



touch, hearing, and smell. 



They are composed of a great 



mimber of joints, and in Butter- 

 flies they are long and straight, 



and are thickened into a club 



at the extremity. In Moths 



the antennae are sometimes 



simply filiform or thread-like, 



but are more frequently pro- 

 vided with appendages, varying 



in shape and size. The antennae 



are called dentated, or toothed ; 



serrated, or saw-like; pectinated, or comb-like; and plumose, or feathery, according to the various 



appearances assumed by these appendages. The sexes often differ in the development of the antennae, 

 * The aborted hind legs of the male of Hepialiis are said to be used as brushes to scatter round him the odour contained 



in two pouches with which his abdomen is provided. 



ANTENN7E OF LEPIDOrTEIlA, GKEATLY MAGNIFIED. 



