378 PTEROPHORUS BALIODACTYLUS. 



PTEROPHORUS BALIODACTYLUS. 



Plate CLXIV, fig. 8. 



On the 31st of May, 1879, I received from Mr. 

 William H. Grigg, of Bristol, seven larvse feeding on 

 the leaves of the top shoots of marjoram, Origanum 

 vulgare. 



They bite practically through the stems near the tops 

 of the plant, causing them to bend down and wither, 

 which is the sign betraying the presence of the larvas ; 

 moreover they eat large holes through the leaves as 

 well as portions out from the edges. 



The full-grown larva (which I figured on the 2nd of 

 June) measures half an inch in length ; the thoracic 

 segments are the stoutest part of the body, from 

 which it tapers a little to the small rather roundish 

 head, and tapers a little very gradually to the anal 

 tip ; the segments are plump and well-defined. In 

 colour the head is pale greenish dingy yellow (raw 

 sienna), the body lightish green, palest on the thoracic 

 segments, and with a thin paler dorsal line interrupted 

 on the middle of each segment ; the small tubercular 

 dots are darkish brown, and from each about six 

 whitish curved bristly hairs radiate at the base, and a 

 seventh longer and blackish tipped proceeds from the 

 centre of each tubercle ; in front of the face, just 

 above the mouth, are two remarkable bristly hairs, 

 their tips curving outwards and black ; the front 

 margin of the second segment is very bristly. The 

 segmental divisions are pale yellowish-green. The 

 spiracles are of the ground colour, extremely minute, 

 ringed (circular) with dull red. The ocelli are black 

 and distinct. The head is small and partly retractile 

 within the second segment. The hairs on the belly 

 are shorter than the others ; on the third and fourth 

 segments the skin between the tubercles is studded 

 with short bristly rudiments of hairs. The hairs 



