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dorsal thread ; at this time when disturbed it is au active little looper, 

 but, otherwise, often hangs by a thread from a twig motionless : when 

 a fortnight old, the dark stripes begin to open into very fine parallel 

 lines. At the age of five weeks, it is a little more than three-eighths 

 of an inch long, of uniform moderate substance, with anal legs well 

 developed, ground colour light brown, with darker lines and paler 

 edges to them, showing much of the characteristics of the mature 

 state, viz., blackish sub-dorsal and lateral marks at the hinder parts of 

 some of the segments, and thick blackish dashes below the spiracular 

 region ; the ventral surface dark brown with paler lines ; it is now 

 rigid and stick-like, and as it has the habit of drawing the anterior 

 legs up in a bunch close to the head, and as the anal legs are stout and 

 thick, it has the appearance of being stoutest at each end. 



During the winter it seems to grow a little, and towards the ap- 

 proach of spring its length varies from half an inch to five-eighths, 

 and the stoutness in proportion : as it approaches full growth its 

 ravages become apparent ; it often eats away all the leaves ou one side 

 of a yew stem before attacking those on the opposite side ; and when 

 it has quite stripped the end of a twig it still keeps to the bare stick 

 as a comfortable resting-place, returning to it, even after feeding at 

 some distance, by help of the strong silk thread attached to the twig 

 from its spinneret, just as in its more juvenile days ; at this more 

 mature age, however, the thread is not easily broken, and always 

 drawn forth in its leisurely progress, both on leaving and regaining its 

 bare stem, to stretch itself along it at full length and embrace it with 

 its legs as its settles itself for a day's sleep : it seems to be only at 

 night that it feeds or moves, unless disturbed, for when I had three 

 or four examples asleep on twigs openly before me for many hours, no 

 movement occurred beyond the mere expulsion of a pellet of frass 

 at intervals ; probably, at large, on a yew tree it would be completely 

 hidden from view. 



The full-grown larva measures one and a half inch in length, and 

 about three-sixteenths, or nearly, in diameter throughout, though the 

 head is a little less than the second segment, its lobes rounded and 

 well defined on the crown ; the segmental divisions indicated by a fold 

 of the skin ; beyond the thoracic segments each has two faint wrinkles 

 anteriorly across the back, and three or four towards tlie end, rather 

 deeper on the sides where the skin is niucli puffed and puckered, 

 especially along the spiracular region ; tlic muscles of the ventral and 

 anal legs largely developed ; the tubercular warts rather prominent, 

 especially the hinder dorsal pairs, which are larger thai} the front pairs, 

 and as well as those along the sides are on little tumid eminences ; of 



