Regeneration in Larval Legs of Silkworms. 595 



day sold; that is, between the first and second mouhing. Collo- 

 dionization of the wounds was first tried, as it was beheved that 

 with such a turgid body and with the kind of circulation possessed 

 by the silkworm the loss of blood-lymph would be considerable. 

 It was soon noted that the blood loss was small and the wound 



Fig. 1. 



Fig. 2. 



Fig. 1. Normal leg of third thoracic segment of fiill-grown larva. 

 Fig. 2. Normal abdominal prop-leg of full-gro^mi larva. 



quickly closed in nearly all cases. Most of the worms, roughly 

 about 80 per cent, lived, and went through their subsequent 

 moultings normally. After the second moulting, which was the 

 first moulting after the loss of the legs, the wounds were always 

 cleanly covered over by new skin, and no sign of regeneration 

 nor of scar was apparent. After the next moulting, however, some 

 specimens would show a certain obvious degree of regeneration, 

 both thoracic and prop-legs being replaced more or less nearly 

 completely as regards number of segments, size, and character 

 of the distal tip. Some specimens would however show no 

 regeneration at all. Nor would these non-regenerating indivi- 

 duals show any change after the later (last) moulting. This 

 was also apparently true of the regenerating individuals also; 

 that is, the amount or character of regeneration shown after the 

 second moulting after mutilation was not increased or changed 

 in the later life of the larva, which has regularly another moulting 

 before the time of spinning up and pupation. 



The unevenness of the results in these cases, both in degree of 

 regeneration and in the regular occurrence of a few cases of no 



