408 Development of the male appendages in Lepidoptera, 



to guide its emergence at pupation. The invaginated 

 constituents of Herold's corpuscule forms the clasps, which 

 present evidence of being ectodermal structures. The 

 portions of the corpuscule of internal origin form the penis 

 and penis-sheath, which never show any evidence of 

 dermal origin, such as hairs, scales, etc. 



I have also seen Professor Meisenheimer's recent essay 

 on experiments by way of excision, transplantation, etc. 

 Ziparis dispar as a very abundant and hardy insect was 

 the subject of his experiments as it was of mine and 

 many others. The species being the same, the interesting 

 result is that where Professor Meisenheimer excised the cor- 

 puscule of Herold in the larva, the imago presented precisely 

 the same development of the ninth and tenth segments as 

 it does in my specimens with the corpuscule imprisoned, 

 but of course in his specimens there is a vacancy where 

 mine show the internally developed appendages. 



Explanation of Plates XXXVII, XXXVIII. 



Fig. 1. Last three abdominal segments of $ L. dispar x 10. 



Fig. 2. Last segment x 25 showing normal structure and disposition 

 of the ^ appendages. 



Fig. 3. Specimen in which the point of exit of the ^ appendages was 

 occluded in the larval state x 10. 



Fig. 4. Portion of the same specimen x 25. These compared with 

 figs. 1 and 2 show the ninth and tenth abdominal segments 

 as in figs. 1 and 2,but without the special sexual appendages, 

 which form a mass lying in the sixth abdominal segment. 

 In this mass the aedoeagus is obvious, as also the clasps, 

 the latter enlarged by still possessing their pupal enve- 

 lopes. The organs so conspicuous in the seventh segment 

 are merely the spiracles, as may be seen by comparing 

 with other segments and specimens. 



Fig. 5. Is a similar specimen x 10, in which the mass has made a 

 nearer approach to the outlet without however breaking 

 through. 



Fig. 6. An intermediate specimen with the mass in the eighth 

 segment. 

 It is very possible that the position of the mass (Herold's corpuscule 



developed) within the abdomen is accidental and due to movements 



during preparation of the specimens, figs. 3 and 4 being perhaps least 



disturbed thereby. 



Within one of the clasps in each specimen (figs. 3, 5, 6) is a dark 



body whose nature I have not determined. In fig. 6 is a separate 



portion, which is probably a detached pupal covering. 



