114 



INHERITANCE IN GUINEA-PIGS. 



any of the 5 known sets of color factors. Four of the sets of color 

 factors, those in which non-agouti (a), yellow (e), brown (b), and 

 albinism (C a ) are the lowest recessives, are known to be independent of 

 each other (Part I). As regards the pink-eye factor (p), it is merely 

 known that cross-overs occur between it and non-agouti, albinism, 

 and yellow, and that it is not an allelomorph of brown (i. e., pink-eye 

 X brown gives black-eyed intense young). 



Data on the possible repulsion of R and A are furnished by cross 72- 

 1, 2, 5, 6, 8, 9, 10 and cross 64-1. Coupling data are to be found in 

 64-3 and 66-1, 3. 



TABLE 58. 



There is an excess of cross-overs. The most probable interpretation 

 is that there is no linkage. 



Data on the coupling of A and S are to be found in crosses 70-1 to 9, 

 71-1 to 6, 72-1, 2, 3, 4, 5, 6, 8, 9, 10, 64-1, and 74-1. Repulsion data is 

 to be found in 64-3 and 72-5. 



TABLE 59. 



A and S are quite clearly independent of each other. 



Crosses 72-5 to 7 give a few data on the relation of R and S to C. 

 We find in the case of R and C, 4 linkages to 4 cross-overs and in the 

 case of S and C no linkages and 3 cross-overs, indicating probably 

 independence in both cases. 



From cross 72-7 we find that cross-overs can occur between R and E, 

 R and B, and S and B. From 61-1 we find that cross-overs can occur 

 between P and R, and P and S. 



Summing up : R is quite certainly independent of S and A and cross- 

 overs are known between it and all of the other known factors E, B, C, 

 and P. S is quite certainly independent of A and cross-overs are known 

 between it and B, C, and P, but not as yet E. It is hoped that more 

 definite statements can soon be made on these points. 



