392 Dr. T. R. Fraser on the Moth of the Ordeal-Bean. 



the bean, as, supposing the kernel to be received into its ali- 

 mentary system, the existence of a special assimilative selection 

 might be shown, or it could be determined if the caterpillar 

 were proof against this deadly poison. 



That the kernel is received into the digestive system is evinced 

 by the presence of the characteristic starch-granules in the ex- 

 crement, and is rendered certain by the following experiment. 



{Exp. 1.) A small piece of kernel, weighing exactly 7 grains, 

 was placed in a porcelain vessel with six active caterpillars. At 

 the end of forty-eight hours, the kernel was found to have lost 

 one grain in weight, and to have two holes (almost perforations) 

 on its inner surface, of nearly the same form and size as those 

 which occur through the spermoderm. The caterpillars were 

 active and lively, and continued so six days after. A quan- 

 tity of excrement was found in the dish, with the characters 

 already described. 



That the starch-granules of the kernel were not received into 

 the alimentary system separated in any way from the poisonous 

 principle was shown by the following experiments with the 

 excrement. This was carefully separated from the numerous 

 aggregations found outside the bean, to avoid as far as possible 

 any admixture with broken-up kernel. 



[Eccp. 2.) One detached fragment was washed, then tritu- 

 rated with a little water, and a drop of this applied to the con- 

 junctiva of a rabbit. In six minutes, it caused a contraction of 

 the pupil, which became extreme in ten. 



{Ewp. 3.) Half a grain of the detached cylinders of excre- 

 ment was triturated, moistened, and formed into a small pill, 

 which was placed in the pharynx of a linnet. Perfect paralysis 

 of the legs was caused in four minutes, together with marked 

 contraction of the pupils (from -rwth to ^nd of an inch in diam.), 

 defsecation and lachrymation. In seven minutes, life was extinct. 

 The post-mortem appearances showed that death had occurred 

 by syncope. 



From these experiments it was evident that no bad conse- 

 quences resulted from the presence of the active principle of the 

 bean in the alimentary canal of the caterpillar. To determine 

 the result of an introduction into the vascular system, experi- 

 ments 4 and 5 were tried. 



{Exp. 4.) An incision was made through the epidermis of a 

 lively caterpillar, and a little of the active principle of the bean 

 (the alkaloid eserinia) was introduced. No evident effect was 

 produced, and the caterpillar was quite active four days after- 

 wards. 



{Exp. 5.) With Wood's hypodermic syringe, half a minim of a 

 solution of eserinia (a grain to 8 minims of distilled water) was 



