310 Mr. Foulton's fii r til er notes upon the 



anterior part of the body rhythmically to and fro for a 

 considerable time, while holding by their claspers. 

 When disturbed they sometimes fall with a thread, but 

 generally quite passively, bending the body into a 

 iventrally concave) \J, and remaining in that position 

 for a long time. In this attitude the head and three 

 thoracic segments are bent backwards, and the true legs 

 folded upwards towards the head, while the anterior 

 pair of claspers are bent backwards towards the last 

 pair. This attitude is sometimes imperfectly assumed, 

 but, if the larva be further disturbed, all the details are 

 carried out in full. The favourite attitude of rest is that 

 shown in fig. 15, Plate VII., the back being curved so 

 that the head is only slightly raised above the supporting 

 surface. In this position the rhythmic lateral move- 

 ments often result from gentle disturbance, and also 

 occur spontaneously. The body of the larva is nearly 

 cylindrical, the head being much the widest part, and, 

 after this, the region of the posterior claspers ; the 

 intermediate part being nearly uniform, but becoming 

 slightly wider towards the extremities. The ground 

 colour is black, as seen from above, but in many speci- 

 mens the two anterior thoracic segments, and those 

 behind the 5th abdominal, are lighter in colour, the 

 hind part of the hind claspers and anal flap being 

 lightest. The sides and ventral surface are brown, of 

 which the shade varies in depth in difterent individuals. 

 There are four white intersegmental bands across the 

 back, in the central part of the body, separating the seg- 

 ments from the 1st to the 5th abdominal inclusive. These 

 bands are made up of irregularly- shaped white spots, 

 which produce the effect of a continuous stripe upon a 

 superficial examination. The first band is the most 

 distinct, but they are all very prominent, because of 

 their strong contrast with the ground colour. Only the 

 first band is continued ventrally (much less broad), 

 while the others cease at the spiracular level, where 

 they are broadest. The head is not of the common 

 Geometer shape, with a deeply-notched crown, nor does 

 it present any of the other irregularities so often met with 

 in this group. It is rounded and lobed by a mesial line, 

 which divides below enclosing a white or greyish triangular 

 mark (the clypeus) above the labrum, which is also light- 

 coloured. The rest of the head is black. The whole of 

 the body is thinly clotlu'd with line long hairs. There 



