290 BRITISH LEPIDOPTERA. 



laterally, is conspicuously pale. The hairs on the head and front of 

 the pro- and mesothorax, long and porrected as in the larvae of the 

 Fumeas. The general colour of the abdomen is dark-red or chocolate, 

 the coloration fainter in the grooves of the lateral flanges, &c, but 

 practically there are no pale markings. The anal plate is dark 

 brownish. The corneous plate of the trapezoidal tubercles and the plate 

 internal to i form, very sharply, the ridges noted as characteristic of 

 the Fumeid larvae. The plumpness of individual larvae may have 

 much effect on the prominence of these, but the larva is not so plump 

 as those of the Fumeas, and, for this reason, the pale dots are at first 

 invisible, but are detected easily enough when looked for. The plates 

 for tubercles i and ii are very distinct, forming summit ridges to their 

 respective subsegments ; tubercle i is placed well in front of, but also 

 well outside, ii ; the hair on iii is porrected ; the prolegs have the usual 

 Psychid pear-shaped margin of hooks, open at the inner end (Chap- 

 man. June 12th, 1899, from larva taken by "Whittle at Eastwood). 

 The young larva (occupying a case 2mm. long, November, 1899) has 

 the head quite black, the labrum, jaws, and other mouth-parts brown. 

 The first thoracic plate is large, black, without line or division ; the 

 mesothoracic plate is about half the width of the prothoracic, brownish 

 in colour, and with a central pale line or division, and a marginal 

 plate below ; the metathoracic plate does not appear to be continuous 

 across the dorsum, and the darker (brownish) portion of it is quite a 

 small patch and away from the middle line. (These characters show 

 a definite approach to Luffia.) The remainder of the dorsum is 

 pinkish-brown, with apparently the same arrangement of tubercles 

 and light spots as in the fullgrown larva. The legs are large and 

 strong, pale brown, much darker along the outer border. The prolegs 

 are marked by about 16 corneous points or hooks. The nervous cord 

 is very conspicuous ventrally, the double brownish -yellow ganglia 

 being very large. The halfgrown larva (from a case 5mm. long) has a 

 black head, the prothoracic plate black, with a very narrow white 

 median line, not reaching the anterior border. The legs and mouth- 

 parts are very dark but not quite black ; the mesothoracic plate, paler 

 than the prothoracic, is relatively rather wider than in the small larva, 

 has a central pale line and a pale longitudinal shade half-way between 

 this and its lateral border, the lower plate dark ; the metathoracic 

 plate is very pale, but appears continuous across the dorsum. The 

 hairs on the head and thorax of all these larvae are very long, more 

 than half the larval diameter (Chapman. November 20th, 1899). 



Comparison of larv;e of Proutia betulina and Bacotia sepium. — 

 The larva of B. sepium has a black head and thoracic plates, relieved 

 on the thorax by only a median whitish line ; that of P. betulina has 

 brownish subdorsal markings (approaching those of F. casta larva). 

 In B. sepium the metathoracic plate is represented by only a small 

 scrap on either side, in P. betulina it is complete across the dorsum, as 

 in F. casta. The colour of the abdominal segments in B. sepium is 

 sepia, in P. betulina it is a ruddy- or pinkish-brown. Their structure 

 is very different ; the abdominal segments in P. betulina are divided 

 dorsally into two distinct ridges, carrying respectively the anterior and 

 posterior trapezoidal (i and ii) tubercles. In B. sepium there is no 

 such definite division, and the tubercles are in transverse alignment 

 (approximately) with the anterior tubercle (i) external (Chapman). 



