TELEGONY AND REVERSION. 133 



similar " shadow " stripes also occur in a small bay Clydes- 

 dale mare's hybrid ; only in this case obscure stripes are 

 found between the vertical body stripes as well as on the 

 neck. It is almost inconceivable that by variation there 

 could be produced in a single generation not only what 

 seems to be the typical number of neck and body stripes 

 for a zebra-horse hybrid, but also shadow stripes, i. e. 

 markings which mimic stripes in process of disappearing 

 in some of the living zebras. By the reversion hypo- 

 theses their presence is easily understood, but to account 

 for them by saying they are the result of abrupt or dis- 

 continuous variation seems to me to be alike unnecessary 

 and illogical. Taking into consideration all the facts above 

 enumerated, I am strongly inclined to the view that in 

 Eomulus and this year's crop of hybrids we have not new 

 and striking variations, but more or less accurate restora- 

 tions of certain remote ancestors, or an attempt to create 

 the hypothetical " mid-parent " of the remote ancestry ; 

 in other words, we have strong evidence that under certain 

 circumstances quite as pronounced reversion occurs in the 

 Equidse as in pigeons. 



It thus appears that when the colour and markings of 

 Norwegian and other ponies are considered, the conclusion 

 seems warranted that all the diiferent breeds of horses 

 have descended from yellowish-brown hog-maned ances- 

 tors, striped somewhat after the fashion of the mountain 

 zebra {Equus zebra). Further, by taking into considera- 

 tion the plan of the striping in the various living zebras, 

 it may be inferred that of all the recent varieties and 

 species the Somali zebra is in many respects the most 

 primitive in the pattern of its decollation. It has also been 

 shown that the five zebra hybrids already bred neither 

 resemble their common sire, nor agree in their markings 

 with Norwegian and other ponies, nor yet stand midway 

 in colour, marking, &c., between their immediate ancestors. 

 When due allowance is made for inbreeding in the respec- 

 tive dams, the conclusion seems inevitable that the remark- 

 able differences between the hybrids and their immediate 



