author's abstract of this paper issued 

 by the bibliographic service, december 9 



THE EFFECT OF ADRENIN ON THE PIGMENT 



MIGRATION IN THE MELANOPHORES OF 



THE SKIN AND IN THE PIGMENT 



CELLS OF THE RETINA OF 



THE FROGi 



ANDREW JOHNSON BIGNEY 



The purpose of this paper is to discuss the influence of adrenin 

 on the pigment migration in the dermal melanophores and the 

 retinal pigment cells of the frog. It seems to be fairly well es- 

 tablished by the work of a number of investigators that adrenin 

 does induce a migration of the pigment granules from the cell 

 processes into the body of the cell of the dermal melanophores of 

 fishes, amphibians and reptiles. This has been proved in the 

 frog by Corona e Moroni ('98) and by Lieben ('06). According 

 to Klett ('08), the retinal pigment of the frog also migrates into 

 the body of the cell under the influence of adrenin, but Fujita 

 ('11) states that this drug produces just the opposite effect on 

 this pigment. In order to clear up this uncertainty and to de- 

 termine the relation of the retinal migration to that of the skin, 

 the present investigation was undertaken. The work was sug- 

 gested by that of Redfield ('17) and was done under the direction 

 of Prof. G. H. Parker, to whom I make due acknowledgment for 

 his many valuable suggestions. 



The frogs used in these experiments were almost entirely Rana 

 pipiens Schreber, though a few of Rana clamitans Latreille were 

 used, but there was no difference seen in the migration of the 

 pigment in either the skin or the retina of these two species. 

 The adrenin employed was that prepared by Parke, Davis & 

 Co. and sold under the name of "Adrenalin Chloride in strength 

 1 to 1000." 



1 Contributions from the Zoological Laboratory of the Museum of Compara- 

 tive Zoology at Harvard College. No. 314. 



391 



