27 



the way of elevated ridges, tubercles, setae, etc., and in some of the 

 Papilionoidea, particularly in the families Hesperiidae and Lycaeni- 

 dae, there seems to be a definite external closing apparatus in many of 

 the genera. Sometimes there is a tuft of setae; in others, a plug or 

 plate of somewhat honeycombed appearance. 



Meso thoracic Legs. — These are folded in exactly the same man- 

 ner as the prothoracic legs and the femora are very seldom exposed, 

 but may be seen in Figure i, f2. The coxae are frequently visible 

 (Figs, i and 48, cx2). The mesothoracic legs are usually longer than 

 those of" the prothorax. The tibia and tarsus of each leg are always 

 exposed (Figs. 1, 8, 23, 30; 1 2 ). They lie on the venter, between the 

 prothoracic legs and the antennae. 



Mesothoracic Wings. — The wings of the mesothorax almost con- 

 ceal those of the metathorax, except in the most generalized forms 

 where the appendages are free. In most families they are the only 

 wings visible on the ventral surface (Figs. 1, 8, 36, 41 ; wi). 



Tegulae. — The tegulae are the large lobes which, in the adult, 

 cover the proximal end of the wing. They do not form separate pupal 

 pieces but are indicated in some pupae (Fig. 2, t). The tegulae are 

 referred to by many authors as the patagia. The patagia are lobes of 

 the pronotum which project over the mesonotum. 



Alar Furrows. — The furrows along each lateral margin of the 

 mesonotum are designated as the alar furrows. They are best devel- 

 oped in the Aegerioidea (Fig. 37, af ) although there are distinct de- 

 pressions in many families. 



Axillary Tubercles. — In the genera Tropaea and Telea of the 

 Saturniidae, there is found a large tubercle at the base of each wing, 

 with sometimes an additional smaller one. The edges of these 

 tubercles are strongly chitinized and somewhat roughened, and serve 

 to cut the cocoon for the emergence of the moth. They are probably 

 assisted in this by the peculiar development of the wing sclerites of the 

 preimago, which protrude into these tubercles and are sometimes 

 found to have cut the pupal skin at the apex of the tubercle. 



Metathorax. — This segment is longest in generalized forms, where 

 its length is nearly equal to that of the mesothorax. 



Metathoracic Legs. — The tibiae and tarsi of the metathoracic legs 

 are never normally exposed for their entire length but are concealed 

 by the other appendages excepting at their distal end. Only a small 

 portion is visible in specialized pupae, and the appendages are often 

 wholly concealed (Figs. 2, 8, 36, 45; L). 



Metathoracic Wings. — These are usually covered by the meso- 

 thoracic wings except for a narrow strip along their dorsal margin. 



