.268 THE entomologist's record. 



eye-spots can be counted. AVlien full fed tliere is a pale dorsal line and 

 a pale lateral region ; this is characteristic of the full-fed larva in the 

 second, third, and fourth skins. 



In the third skin the larva is of similar character, the pale dorsal 

 line and pale lateral region are more evident, and more distinct in tint 

 from the intermediate darker region. The hairs are more numerous, 

 the tubercles being large bosses carrying them stellate fashion, the 

 posterior trapezoidal and supra-spiracular being very large, the others 

 smaller, but each with many hairs ; the ventral prolegs have six 

 strong hooks, and an extended flange, as if for more, both before and 

 behind them. Th<! anal prolegs have the same structure. The tnie 

 legs still carry a laige battledore palpus, or a pulvillus. 



In the fourth skin the length extends to twelve mm. and the hairs 

 and tubercles are disposed as in the last skin. The supra-spiracular 

 tubercles and those below them tend to have white summits. This is 

 so more or less in all the folloAving skins, and full grown larva3 often 

 have tubercles with a white, silvery sheen. A few of the longer hairs 

 are whitish, and the white dorsal line is more distinct, but varies much 

 in width. The prolegs have 9-11 well developed hooks, and the 

 extended flange bej^ond is now plainly marked by chitinous lines, 

 plainl}' the rudiments of 5 or 7 more at either side. 



In the fifth skin the hairs are more crowded than previously, and 

 though the dorsal and lateral pale lines are plain enough, they are not 

 (owing to the greater density of the hairs) so obvious as in previous 

 skins. The prolegs have twelve and thirteen hooks, and i^laces for 

 seven or eight on either side, disposed precisely as in the previous skin. 



It is in this fifth skin that hybernation takes place. As illustrating 

 the difficulty of dealing with moults, I maj^ say that two good observers 

 both told me that with them the larvae hybernated in the second skin, 

 but when shown the larva in the fifth skin, said, yes, that was the size 

 in which they hybernated. After hybernation the larva moults three 

 times more, but not unfrequently only twice, probably according to 

 the successful h^djernation as regards exhaustion or otherwise, whilst 

 four moults may occur. In all these, however, the larva now has the 

 plumage of the adult larva, that is, long flowing black hairs with 

 whitish tips, paler lateral hairs, and red hairs in the front segments. 



For my own convenience I have called this the caia plumage (PI. I., 

 fig. 4 ; PI. II., fig. 5). That of the fifth skin, in which the hairs are 

 very dense, of tolerably uniform length, and also of a tolerably uniform 

 tint, rarely much redder in front, I have called the fnliy/aosa plumage, 

 as the larva resembles the full-grown larva of A. fidiginosa (PI. I., 

 figs. 2 and G ; PI. II., fig. 4), and, like it, the hairy clotliing seems adajited 

 to hybernation. The earlier skins, with fewer hairs and the larval 

 skin more in evidence, I have called the Spilosonta ^jlumage (PI. I., 

 figs. 3 and 8 ; PI. II., fig. 2). 



AVhetiier I was led to the names by the considei'ation of what these 

 resemblances probably suggested, or whether the suggestion originated 

 with the names, I have not been able to avoid theorising that, in habit, 

 as regards the hybernation of the larva, we begin with Sj^ilosoma 

 (menthastri), Avhich has a delicate larva, and hj-bernates as a pupa. 

 A similar delicate larva in fidifjinosa becomes very hairy and robust in 

 its last skin for hybernation ; whilst caia goes a step further, and 

 assumes a further and different plumage after hybernation. 



{To he continued.) 



