THE PENYCUIK EXPERIMENTS. 127 



heredity and variation, and until we know more about the laws which 

 govern these factors we can not hope to arrive at any satisfactory criteria 

 by which we can estimate the importance of the data accumulated for 

 us by comparative anatomists and embryologists. Signs are not wanting 

 that this view is beginning to be appreciated. The publication of 

 'Materials for the Study of Variation/ by Mr. Bateson, a few years ago, 

 shows that there exists a small but active school of workers in this 

 field; and the recent congress on hybridization, held in London under 

 the auspices of the Eoyal Horticultural Society, is evidence that in 

 America, on the Continent and in Great Britain one of the most im- 

 portant sides of heredity is being minutely and extensively explored. 

 Prof. Cossar Ewart's experiments, which we shall attempt to summarize, 

 deal with heredity and cognate matters, and, although they are so far 

 from complete that the results hitherto obtained can not be regarded 

 as final, they mark an important stage in the history of the subject. 



Five years ago Professor Ewart began to collect material for the 

 study of the embryology of the horse, about which, owing to the costli-, 

 ness of the necessary investigations, very little is at present known. At 

 the same time he determined to inquire into certain theories of heredity 

 which have for centuries influenced the breeders of horses and cattle, 

 and the belief in which has played a large part in the production of our 

 more highly bred domestic animals. Foremost among these is the view 

 widely held among breeders that a sire influences all the later progeny of 

 a dam which has once produced a foal to him. This belief in the 

 'infection of the germ,' or 'throwing-back' to a previous sire, is 

 probably an old one — possibly as old as the similar faith in maternal 

 impressions which led Jacob to place peeled wands before the cattle and 

 sheep of his father-in-law Laban. The phenomenon has recently been 

 endowed with a new name — Telegony. Since the publication of Lord 

 Morton's letter to Dr. W. H. Wollaston, President of the Royal Society, 

 in 1820, it has attracted the attention not only of practical breeders, 

 but of theoretical men of science. The supporters of telegony, when 

 pressed by opponents, having almost always fallen back on Lord Mor- 

 ton's mare, it will be well to recall the chief incidents in the history of 

 this classic animal. 



It appears that early in this century Lord Morton was desirous of 

 domesticating the quagga. He succeeded in obtaining a male, but, 

 failing to procure a female, he put him to a young chestnut mare, of 

 seven eighths Arab blood, which had never been bred from before. The 

 result was the production of a female hybrid apparently intermediate 

 in character between the sire and the dam. A short time afterward 

 Lord Morton sold his mare to Sir Gore Ouseley, who bred from her by 

 a fine black Arabian horse. The offspring of this union, which were 

 examined by Lord Morton, were a two-year-old filly and a year-old colt. 



