TRIFID.E. 



291 



in inland rocky localities seems to be in the direction of 

 yellower colour and more obscure markings, that on the coast 

 to larger size, greater distinctness of the markings, and 

 sometimes to deeper colour ; yet this is by no means 

 invariable. 



On the wing from the end of August or September to 

 November, then hy be mating and reappearing on the wing in 

 March or April. 



Larva moderately stout, cylindrical, tapering very little ac 

 either extremity, smooth and shining ; the folds and segmental 

 divisions very slightly indented ; a triangular inflation round 

 the spiracles ; the raised spots shining and the legs well 

 developed. Head brownish-red ; mouth dark brown ; on the 

 back of the second segment is a reddish shining plate divided 

 down its centre by a thin line of flesh-colour, thickly 

 margined in front — where it is widest — and more delicately 

 behind with dark brown. General surface flesh-colour, 

 having the pulsating dorsal vessel visible as a stripe of a 

 darker tint of the same ; the raised spots are brown and 

 conspicuous, generally round, but sometimes oval on the third 

 and fourth segments ; on these segments also they are placed 

 in a transverse row on the back and end at the sides in a 

 triangular group of three larger spots ; altogether there are 

 twelve spots on each of these thoracic segments, the other 

 segments to the twelfth inclusive have the usual two pairs on 

 the back of each and the thirteenth one pair, the anterior 

 larger than the posterior pair and all gradually diminishing 

 in size from the fifth to the eleventh segment, but on the 

 twelfth they become larger again and are there transversely 

 oval in shape ; each spiracle has a large round spot above 

 and below it, another behind, and a small one in front of it ; 

 these two last mentioned are sometimes both small and some- 

 times one of them is absent, but the two that are above and 

 below the spiracles are larger than any upon the back. 

 Spiracles oval, whitish outlined with black ; on the anal 



