141 



THE EFFE("r OF ADUEMX OX THE PKIMEXT ]Ml<;UATIOX IX THE 



MELAXOPHOKES OF THE SKIN AXD IX THE I'lUMEXT CELLS 



OF THE KETIXA OF THE FKOG. 



Am>1{i:\\ J. P.I(;.m;v. I'lv.-iiisvillc ('(ilk'iio. 

 (Autlior's Al.stract) 



(The orifiiiial printod in "Tlic Joui'iial of E\p(>riiii(>ii(al /(.(.loixy" Vol. 27, 

 Xo. :;. January. lOlO. ) 



The tvoiis usi>(l wci-e mostly Kaiia idpiciis Sciirchcr. Tlic ;i<liriiiii ciii- 

 ployed was that prepared by Parke. Havis vV;: Co., and sold under the name 

 of Adrenalin Chloride, in strength 1 to l.ddO. 



In the melanophores of the skin, tlio pi;,Mnciit in (he li.nht expands, while 

 in the dark it contraets. On in.jcetiiiu- adreinn in frotrs winch had been 

 in tlH> ll.uht for six hours, it was found that I lie melanophores were strongly 

 contracted. The effect being opposite to that of light. The adrenin 

 1 :1()00 and 1 :10000 strength gave the best results. 



The migration of the retinal pigmeid is outward in the light and into the 

 cell in the dark. On injectuig X)C, cc of adrenin. 1 :1()0() into frogs kept six 

 hours in the light, the pigment was found to be fiUly expanded after 7-Lj 

 minutes exposure. Then other frogs were kept in the dark six hours and 

 injected with same amount of adrenin and the pigment was also expanded. 

 Control frogs in the dark showed the pigment contracted. So the conclu- 

 sion was reached that the adrenin has the same effect as light. The retinal 

 pigment was sensitive in sctluticns from 1 :1(M)0 to 1:1000000 and remained 

 for three to four hours. 



The effect on the dermal melanophores is Just the oiijiosite to that on the 

 retinal pigment. This is new to science. 



In the above experiments, the frogs were decapitated, eyes removed, 

 hardened in Perenye's fluid, imbedded, sectioned, and mounted unstained. 



