STRYMON PRUNI. 



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red line (median suture) on the front half of the mesothorax. Within 

 a minute the white areas of the mature papa (prothorax, portions of 

 mesothorax, metathorax, and 1st abdominal segment) show a slight 

 opacity, which gradually increases till, at the end of twenty minutes, 

 it is really white, the rest of the pupa being still green ; the thorax 

 and appendages pale and bright, but the abdomen already distinctly 

 darkening. The hollow of the slopes are, by this time, mature ; they 

 were indicated within five minutes of the moult ; the spiracles also are 

 now prominent, and the pupa may be called mature as to form ; the 

 mesothoracic dorsal hump is hardly fully formed, but the mesothorax 

 rises from the waist. The raised spiracles are on pale transparent 

 bases, and form white dots along the sides, the spiracular line or slit 

 proper being very white, and, by refraction, making the humps (bases) the 

 same. 5 p.m. : At the end of half-an-hour the abdominal venter, so far 

 as visible, is white, the dorsum darker, but still green, and the colour 

 of dorsal spines only a little less bright than at first. On dorsal view 

 the thorax is still white and pale green, not very different, the abdo- 

 men decidedly darker ; the broad abdomen and narrow thorax are those 

 of the mature pupa. 5.30 p.m. : White is very white; the thorax 

 still green ; the dark of abdomen deep olive, the colouring of humps still 

 distinct. A point that has escaped observation is now noticed, in 

 consequence of two marks, already quite black (nothing else being 

 more than olive) ; they are on the front margin of the 2nd abdominal 

 segment, each beginning as a fine point opposite the hump and ending at 

 the hollow, half-way to the spiracle, being here nearly half the width 

 of the segment. About the middle of these the girth disappears to the 

 same point on the opposite side, and it is obvious that the front 

 margin of the 2nd abdominal segment has rolled over the 1st abdominal 

 segment far enough to cover it. [Examining a mature pupa that moulted 

 last night, these black marks are quite distinct, the other black areas 

 being polished and shining, this is dull.] The girth disappears in the 

 same way. By looking at the pupa from various angles it appears 

 impossible in any way to see the girth across the pupal dorsum. 6 p.m.: 

 The whole pupa is now mature as to colour, and happens to be a very 

 black one, except just above the spiracles ; there is nothing but black 

 over the whole abdominal dorsum, except, of course, the first segment. 

 The most curious part of the pupating process was the mobility of the 

 last segments immediately after the moult ; these were, at that time, 

 apparently actively investigating the cast skin, so as to know best 

 how to deal with it (Chapman). 



Pupa. — In its dorsal aspect a very excellent imitation of a bird's- 

 dropping. The general colour black, with a whitish patch on each 

 side of the anteriorly protuberant prothorax, another on the lower 

 central area of the swollen mesothorax, and a third, somewhat ) — (- 

 shaped, crossing the constricted metathorax transversely, and terminated 

 by the wings. Two other narrow lateral whitish patches run along, 

 one on each side of the abdomen, below the spiracles. These white 

 patches produce a marked effect on the black ground colour, and there 

 can be no doubt that the pattern of coloration is protective. The skin 

 is somewhat wrinkled and thickly covered with short golden bristles, 

 except on the wing-, leg-, antenna-, and maxilla-cases. These are 

 smoother, of a greenish-black hue, and somewhat translucent. Dorsal 

 view : The head is placed ventrally ; the prothorax rounded, bulging 



