4 8 



Scientific Proceedings (62). 



30 (962) 



On the refractive index of the serum in a guinea-chicken hybrid. 



By Raymond Pearl and John W. Gowen. 



[From the Biological Laboratory of the Maine Agricultural 

 Experiment Station.] 1 



In connection with some biochemical studies on heredity now 

 in progress in this laboratory we desire to record certain results 

 regarding the refractive index of the blood serum of a genus-hybrid 

 produced from the mating Cornish Indian Game o 71 X Guinea 

 Fowl 9 . The measurements were made with a Zeiss Eintauch 

 Refraktometer on the unmodified serum of freshly drawn blood, 

 expressed from the clot by centrifugation. 



Our results show that (1) there is a definite, characteristic, 

 and permanent difference between the refractive index of the 

 serum of the fowl and that of the guinea; and (2) that in the 

 hybrid the guinea parent is dominant in respect of the physico- 

 chemical constitution of the blood as measured by the refractive 

 index. Some figures on the point follow: 



Source of Blood. nD 



Fowl (Gallus sp.) 1-34537 



(Mean of data from 10 birds of different hereditary constitutions) 



Guinea (Numida meleagris) 1.34184 



(Mean from 6 birds) 



Hybrid (Callus c? XNumida 9) I-34I79 



31 (963) 



Application of the serum-skin test to the diagnosis of pregnancy 

 and different pathological conditions. 



By J. Bronfenbrenner. 



[From the Pathological and Research Laboratories of the Western 

 Pennsylvania Hospital, Pittsburgh, Pa.] 



As it was shown in previous communications, 2 the dialyzable 

 substances in the Abderhalden test appear as a result of auto- 



1 Paper No. 77. 



2 See last number of Proc. Soc. Exp. Biol, and Med. 



