aitthor's abstract of this paper issued 

 bt the bibliographic service, october 23 



PHYSIOLOGICAL SELF-DIFFERENTIATION OF THE 



WING-GERMS GRAFTED ON CATERPILLARS 



OF THE OPPOSITE SEX^ 



STEFAN KOPEC 



Government Institute for Agricultural Research, Pulaunj, Poland 



■ The development of the pigment in the wings of moths has 

 not yet been sufficient!}^ studied ; there is, however, no longer any 

 doubt that the chief ingredient in the formation of the pigments 

 is the blood, or the so-called haemolymph of the animal. How 

 this formation takes place has not yet been ascertained; some 

 authors believe that the pigment is directly caused by the drying 

 up of the haemolymph. On the contrary, according to Mayer 

 ('96, '97), there are certain ferments in the scale-forming cells 

 which render the formation of the pigment possible. On this 

 ■\-iew the pigment is the product of certain changes which 

 occur in the insect's blood, under the influence of special ferments. 

 Crampton ('00) is inclined to Mayer's opinion, but I think 

 that his notable experiments are not sufficient to demonstrate it. 

 Crampton united various parts of the pupae of the moth Callo- 

 samia promethea by means of paraffin, so that the front part of 

 the body obtained belonged to one sex, the hind part to the other. 

 These bodies developed further until the stage of the adult moth, 

 when each part of the artificially united body showed its specific 

 and dimorphic color, different in front and behind. "We must 

 conclude, therefore," says Crampton, "that the production of the 

 sexually-different ground-colors of the adult moths is determined 

 by some 'ferment' factors which differ in the two sexes, and that 

 the difference in the adult colors is not due to a difference between 



1 Paper from the Embryologico-Biological Laboratory, Jagellonian University, 

 Cracow, Poland, presented in the Acad, of Sc. Cracow. (Cf. Bull. Acad, d, Sc. de 

 Cracovie, 1917.) 



469 



THE JOURXAL OF EXPERIMEXTAL ZOOLOGT, VOL. 36, NO. 4 



