MIMAS TILLE. 415 



on the 3rd abdominal segment. The sculpturing of the abdominal 

 segments, i.e., of their three anterior subsegments, deserves special 

 attention. The roughness of the mesothorax consists of a set of 

 minute raised islets, closely packed together, the top of each having 

 several small rounded projections, this is somewhat modified 

 on the metathorax and in the 1st abdominal ; they consist of a maze 

 of waved ridges, of fairly uniform size and height, running into 

 one another, or as it were dropping under each other; when we 

 reach the 3rd abdominal segment, these ridges are larger towards 

 the front of the segment, smaller behind, and this character they 

 preserve through the rest of the abdominal segments ; they have 

 also very largely arranged themselves into a set of minute 

 semicircular ridges, all with the convexity forwards and all highest 

 on the forward edge, the points of the cusps fading down beneath 

 the crests of those behind them ; these get larger and more 

 pronounced as we pass backwards ; on the 5th abdominal segment, 

 a large number of them are complete raised rings, with central 

 cups, reminding one of a set of volcanic craters or a lunar landscape ; 

 on the 7th abdominal they are very large and numerous and packed 

 together, but retain the character of being larger on the anterior 

 portion of segment, and with their posterior lips lower, but rarely 

 wanting ; on the 8th abdominal they are large and crowded so as 

 to interfere with each other here and there ; on the 9th and 10th 

 this tendency is much greater, so that on the 10th the condition 

 is rather one of high irregular ridges, with deep pits between them • 

 the same sculpturing occurs all round the segments, but is less 

 pronounced and smaller ventrally, so that these ridges, in front of 

 the spiracles of the 5th, 6th and 7th abdominal segments, are 

 raised semicircles, as described on the 3rd abdominal dorsally, 

 but the individual crescents are more distinct, from having 

 little other sculpturing along with them. Ventrally, on the 

 5th and 6th abdominal segments, are the scars of the 

 prolegs ; these are depressions surrounded by a low, rounded 

 elevation, the bottom of the depression is more or less smooth and 

 flanged, from which radiate, over the surrounding elevation, fine 

 ridges which lose themselves in the general sculpturing of the 

 segment. On the dorsum of the 8th is a very similar scar of the 

 larval horn ; this (like the scar of the prolegs) varies a good deal, 

 it is usually a slight elevation, with a depression behind it ; the 

 ordinary sculpturing radiates from the top of this elevation, as if a 

 bit of it had been cut out and the rest drawn together from all 

 round to fill the vacancy ; sometimes the elevation has a central 

 depression that is smooth and glazed ; in some specimens it is 

 almost obscure, but is never quite absent, so that this pupa does 

 not range itself with those that only present such scars when 

 weakly or not well-developed. The 9th abdominal segment has a 

 small depressed circle in which are, side by side, two rounded 

 elevations ( $ parts); the 10th segment has, as already noted, a 

 wide end, the dorsal portion of which has a cremastral spine, 

 conical, very rough, ending in a minute bifid point ; the larger 

 ventral portion has a depressed central line, with a rounded 

 boss on either side ; these bosses are roughly sculptured, as 

 noted above ; the depressed central line has, on either side, a 



