EXTERNAL ANATOMY OF INSECTS. 641 
are there scolloped into alternate bays and capes, if I 
may so speak, varying in depth and length?. There is 
usually a sinus between every pair of nervures, each of 
which terminates in the adjoining prominence, as a fold 
does in the sinus>. Where present, in the primary wings 
there are eight of these sinuses, and in the secondary, 
where they are most usual, seven ; some are remarkable 
for the long tails which distinguish their secondary wings; 
those in Papilio are usually an elongation of the fifth, 
from the anterior margin, of the prominences before 
mentioned, into a spathula-shaped diverging process, 
varying in length and width ©: but in P. Ulysses it does 
not diverge; andin P. Podaliriusit is linear. They are 
found also in other genera or subgenera ; thus in Urania 
Patroclus there are two ; in U. Ripheus, three ; in Heli- 
copis Cupido, five ; and in H. Endymion, six of these tails ; 
in some, as in Lrycina Dorilas, the whole wing seems 
to form the tail; in others again, as in Uria Proteus, K. 
and Artemis Luna, K. it is an elongation of the anal 
angle. Other wings in this Order are divided into lobes 
resembling feathers, as you may see in Pterophorus 
hexadactylus, &c. 4 
6. Weare next to consider the clothing of wings: these, 
in the Orders in which they are covered by elytra, teg- 
mina, or hemelytra, are generally naked, except that the 
spots in those of Fulgora laternaria, serrata, &c., and the 
whole wing in Flata, Aleyrodes, and others, are covered 
with a kind of farinaceous powder ; but in all the remain- 
* Pirate XIV, Fie. 2. 
» In Gastropacha quercifolia, &c., amongst the Nocturnal Lepi- 
doptera, these sinuses exist, in the upper wing fen, and in the lower 
nine, but without the folds. “ Prate XIV. Fie. 1. s. 
4 Tbid. Fie. 3. 
VOL. Lit. PAM: 
