SOME RESULTS OF OSTRICH I X VESTI(;ATIoXS. 265 



Taiile 3. — Measurciiieut of Eggs of Cross-bred (Ostriches. 



Long Diameter. Short Diameter. 



Series A, lo eggs 6.08 5.08 



Series B, 10 eggs 6.06 5-02 



Series C. 14 eggs 5 .89 5 .09 



•\verage 6.01 5 .06 



The nioasurements of the three series may be compared as 

 follows : — 



Long Diameter. Short Diameter. Difference. 

 43 North African Eggs 6.15 ... 

 34 Cross-bred Eggs ... 6.01 

 20 South African Eggs 5.92 



Though not elaborate enough for many purposes, ti'e results 

 suffice to indicate that as regards size and sha])e the cross-bred 

 eggs are intermediate between those of the nortnern an.d the 

 southern bird. They apparently approach somewhat nearer to 

 the southern than the northern, but with such variable objects, 

 an indication of this kind may be deemed of little value when 

 only small numbers are available. 



The intermediate nature of the cross-bred eggs, as regards 

 size, shape, and the nature of the surface, may be taken to suggest 

 that the different characteristics of the eggs of the two races of 

 ostrich are dependent upon separate factorial representation in 

 the germ plasm, as in the case of the dimensions and colours of 

 the birds. Also the factors are not alternatives, for in r'l'^ 1^^-lirid 

 <ig^ no one character of the parents is donn'nant or recessive to 

 the other, but each strives, as it were, for expression, the result 

 being something midway between the two. 



Nu:mhf.r of Plumes to W'ixg. 



In the prosperous ostrich days before the war the i)lumes pf 

 hundreds of thousands of birds were clipped yearly, yet it is 

 doubtful if many farmers were in a position to tell how many 

 feathers came from the wing of an ostrich, or how many from 

 the tail. In a general way it was known that the wings an.d tail 

 of some birds gave more feathers to the crop than others, but it 

 was impossible to say by how many. This indifference arose 

 partly from the fact that feathers are sold by weight and not by 

 number, but was mainly due to the fact that in the ostrich |)lume 

 quality counts for far more than quantity. In making com- 

 parisons of the plumage of the North African and South African 

 ostriches, and of the cross-breds derived from them, it has been 

 foimd necessary to determine the exact number of commercial 

 feathers produced by each, and this has led to a detailed study of 

 the wing and tail feathers generally. The result has been the 

 discovery of certain facts in connection with the plumage of the 



