STATES OF INSECTS. (Larva.) 175 
In both cases, they form a coating usually so dense as 
to conceal the body, but sometimes more thinly set, and 
admitting the skin to be seen more or less between them. 
In a caterpillar of the beautiful Spzlosoma ocularia, the 
hairs are set upon tubercles alternately nearer the ante- 
rior and posterior margin of each segment, so as to form 
a dense band, the rest being naked; and in the lovely 
green and black one of Saturnia Spini, each tubercle 
bears but six hairs, diverging like a star, the central one 
being the longest and capitate, so that the chief part of 
the body appears naked. This diverging position of the 
hairs is most common in the thick-clothed larve also, 
but many have them placed differently: thus, in those of 
Euprepia Caja and villica® they are all directed towards 
the tail, like the quills of a porcupine: in some others 
the anterior ones point towards the head: in that of 
Lasiocampa Quercus half of the tuft of hairs of each tu- 
bercle is directed downwards, the other half upwards: 
in that of Arctia Salicis all the hairs point downwards, 
so that the belly is thickly covered, while the back is 
bare. Another variation is, that the hairs of half the 
tubercle are sometimes very long, while those of the other 
half are very short, and even of a different colour>. In 
the larva of Tussock moths (Dasychira pudibunda, fasce- 
lina, &c.) the hairs are collected into tufts of a singular 
appearance, those on the intermediate segments of the 
back being quite level at the top, so as to resemble so 
many brushes; while those on the first and last segments 
are longer, and composed of feathered hairs converging 
to a point at their extremity, like a common camel-hair- 
* Sepp. iv. ¢. i. f. 3. é. xvi. f. 2, 3. 
> N. Dict. d Hist. Nat. yi. 254. 
