CALLOPHRYS RUBI. 113 



like small lenticles from which radiate raised ribs. These usually join 

 adjacent points together, but always die out, rather than link up to a 

 hair or lenticle, and thus raising a very marked distinction between 

 these points and those structures. They are most abundant and 

 characteristic some way above the spiracles, where there are fewer 

 lenticles to interfere with them ; they are also well-developed on the 

 thoracic dorsum. The points are much smaller than in the pupa of 

 Thestor ballus, being only about 0'02mm. in diameter ; they appear to 

 have a central point, but any stellate structure as in T. ballus is not 

 obvious. The appendages have neither hairs, lenticles, nor points, but 

 look much as if the ribs connecting the latter had thus their full liberty 

 to develop into a complete and continuous network of a pattern of 

 pleasing sinuous lines, much finer than the broad, patchy-looking ones 

 of the pupa of T. ballus, bat rather thicker than in that of Bithys 

 quercus. The glazed eye has a dark curved line, over which, and 

 interior to which, for a total width of about Olmm., is a finely 

 irrorated area, with hexagonally-disposed points. Interior to this is 

 a,n ordinary skin-area, with points, ribs, and one or two hairs. Out- 

 side it, the surface has narrow ridges, radiating from the glazed eye. 

 The prothoracic spiracle (cover of) is a rounded ridge, Olmm. in line of 

 suture, 0'2mm. across, with a very finely tesselated surface, of which the 

 cells tend to be arranged across the ridge. It is situated unusually far 

 from the antenna, nearly two-fifths of the way from it to the dorsum 

 (Chapman). Very short and thick, especially about the middle of the 

 abdomen, rounded and blunt at the anal tip ; the wingcases nowhere 

 projecting, but smooth and large in proportion, and, like the rest of 

 the surface, unpolished. In colour it is of a dark, dull, purplish- 

 brown, and is thickly clothed with short, dark-brown bristles, 

 excepting only the wing-covers, which are blackish-brown and have 

 none. Its appearance would assimilate well with pellets of earth 

 (Buckler). 



Pupal dehiscence. — The thorax separates from the head, and the 

 antennae separate to some distance from the wings, and a division 

 occurs down the dorsal line of the thorax. Through the opening thus 

 afforded, the butterfly escapes, but the several portions, by their 

 elasticity, at once spring back to their places, and it is not very obvious 

 from the appearance of the pupa that emergence has taken place ; 

 later, however, as the shell dries, it curls to some extent, and, the free 

 edges bending in, destroy the undisturbed appearance. On examining 

 the empty shell it is found that, where no separation has taken place, 

 the p trts still cohere very slightly; the head-cover, with the eye-plates, 

 separates from the appendages, the antennae from the wings, the 

 pro- and metathorax from the mesothorax with wings, and the 

 metathorax and wings from the abdomen, except in front. All these 

 separations seem to occur by fracture, no trace of intersegmental 

 membrane being displayed where they take place. It is different with 

 the abdominal segments. The living pupa seems to be solid and 

 without movable parts, but the dehisced pupa shows always some 

 separation of the 4th from the 5th abdominal segment, and very little 

 violence opens all the other abdominal incisions from 1-2 to 7-8. and, 

 in each case, intersegmental membrane, fully developed as belonging 

 to both the segments concerned, remains and attaches the margins 

 together, looking just as if all these incisions were intended to be 



