220 CRAMPTON. 



ponent which has been deprived by a transverse section of its 

 anterior part, namely, head, prothorax and the basal parts of the 

 limb, mouth-part and antenna sacs. The method of keeping 

 the parts together, by means of melted parafifine applied to the 

 edge of the common wound, has already been described in a 

 communication before this section of the Academy at a meeting 

 last spring. The condition of the pup^ was quite advanced, 

 owing to their being kept in the warm laboratory from the time 

 they were procured in November. But, as is often the case, one 

 of them, the cccropia, was more advanced than the other, and 

 was, indeed, ready to emerge fully five days before the promctliea. 

 Only the posterior portion of the pupal case of the former was 

 removed to permit of the voidance of excreta. When the pro- 

 vietJica was ready to emerge its pupal case and the remainder 

 of that of the cccropia were removed. The compound was 

 supported below a ball of cotton, so that the moths could hang 

 suspended from it, and thus assume the attitude which is almost 

 indispensable for the expansion of the wings. Nevertheless, in 

 spite of all arrangements, the wings of neither component ex- 

 panded, and the colors, therefore, appear on a reduced scale. 

 The wings of the cecropia remained soft and evidently in a dis- 

 eased discolored condition, owing, no doubt, to the prolonged 

 enforced stay in the pupal cases. 



The general appearance of the complex is that of a long 

 body, provided with two sets of wings and legs. The facts of 

 special interest are : first, those of the structural conditions ; 

 and second, those relating to the coloration ; for, although the 

 cecropia wings show no abnormalities aside from their general 

 decomposed condition, the wings of the promctliea exhibit some 

 most remarkable appearances. 



First, the structural peculiarities will be noted. These occur 

 naturally at the region of union between the two components. 

 From the cecropia were cut away the head, prothorax and 

 mesothorax in part, and as well the basal parts of the antenna 

 and palp sacs, and those of the first pair of legs. These parts 

 are all absent in the metamorphosed complex. In dorsal view 

 the fourth abdominal segment of the promctliea is united to the 



