33i 



SCIENCE-GOSSIP. 



MAEKINGS OF THE HORSE TRIBE. 



By Wilfred Mark Webb, F.L.S. 



SOME years ago Dr. Ewart, Eegius Professor of 

 ISTatiiral History in the University of Edin- 

 burgh, began to make a series of experiments in 

 order to throw light upon the vexed question of tele- 



gony. This last word was coined to express the sup- 

 posed inheritance of the characteristics of the dam's 

 first mate by her offspring to a second sire. The 

 case, which, as Professor Ewart says, breeders 

 qiiote in support of the theory with "tiresome 

 unanimity," has reference to a mare belonging to 

 Lord Morton, early in the century. This noble- 

 man wanted to breed quaggas, which have since 

 become extinct, but he could only obtain a male 

 example, and he mated it with a chestnut mare of 

 seven-eighths Arabian blood that had not pre- 

 viously been bred from. A striped hybrid filly 

 was produced, and its mother, after she had passed 

 into the possession of Sir Gore Ouseley, bore two 

 foals to a fine black Arabian horse. The point of 

 the story is that the piire-bred filly and colt were 

 marked more strongly than the quagga hybrid, 

 and, it should be added, even bore stripes in places 

 where there were none in the qiiagga, to whose 

 influence they have always been attributed. 



Professor Ewart has tried to repeat as nearly 

 as possible the featru-es of Lord Morton's case. 

 Quaggas being non-existent, the work was begun 

 with a zebra stallion belonging to the variety 

 known as chajpmani of Equus bwchelli. As the 

 experiments have proceeded, the results, together 

 with many facts collected in their elucidation and 

 the conclusions suggested, have been published at 

 variovis times and in several places. Professor 

 Ewart has now reprinted his papers and written 

 an introduction, which together form a book 

 tmder the title of the " Peny ciiik Experiments " ( ^ ) . 

 One would say that, although we may owe a 

 volume produced in this way to the miuimum of 

 labour it imposes on the author, yet at the same 

 time it causes a maximum of trouble to the 

 student who wishes to obtain a clear idea of the 

 position aiTived at. It is little use making the 

 valuable suggestions and facts with which the 

 book is brimful, for there is no index to enable 

 one to refer to them again. The only course to 

 adopt is one which takes a good deal of time, and 

 that is to make references as one reads the book 

 to such pages as one would wish to find again. 



To begin with, the author says (p. Ixviii.) : 



"I do not by any means say that telegony is 



impossible," but, all the same, he thinks that it 



has not been demonstrated experimentally, and 



that it is "as improbable as the almost equally 



C) " The Penycmk Experiments," by J. C. Ewart, M.D., 

 r.E.S., Eegius Professor of Natural Historj-, Universitj- of 

 Edinlnu-gh. 6 in. x 9in., xciii. + 177 pp.,46flgaires. (London : 

 Adam and Cliarles Black, 1899). 10s. 



common belief that the colour of the offspruig' 

 may be influenced by 'maternal impressions,' as 

 Laban's sheep and cattle are said to have been 

 influenced by the peeled wands of his son-in-law 

 Jacob." 



Fiu-thermore, Professor Ewart prefers to con- 

 sider that Sir Gore Ouseley's colts (p. Ixix.) did 

 not owe their stripes to telegony, and everywhere 

 suggests that these were due to ata"vdsm or ordinary 

 reversion to an ancestral type. This conclusion 

 is arrived at not merely fi'om a consideration of 

 the animals themselves, but also of the many 

 zebra-horse hybrids which have been bred at 

 Penycuik. The following niimbered paragraphs 

 give evidence in support of the contention : — 



( 1 ) It is fairly well established that the ancestors 

 of the horse were striped, and Professor Ewart 

 adds to oiu- knowledge (pp. 105-110) of the markings 

 which occur commonly on the legs, occasionally 

 on the bodies, and rarely on the foreheads of 

 Equus cahallus, the domestic horse. Further, a 

 point which has not been sufficiently investigated 

 is the occvxrrence, particularly in yormg Arabs, of 

 distinct stripes, which, however, do not often 

 persist after the second year. 



(2) The markings of the zebra-horse hybrids do 

 not, when compared in detail with those of their 

 father, agree at all with them. The almost 

 necessary assvunption is that the patterns of the 

 young ones must have come either from the less 

 remote ancestors of the zebra, or from the common 

 ancestors of all the Equidae (p. 134). Compare 

 the stripes upon the head of father and son in the 

 illustrations, kindly lent by the publishers, which 

 form figs. 19 and 20 in Professor Ewart's book ; 

 the markings make parted arches in the first, and 

 circular ones in the second. Again, on the neck, 

 the zebra has but twelve stripes, on the sides less 

 than ten, while the hybrid has twenty-four and 

 forty -three respectively. 



(3) Lastly in this connection, the second foals 

 produced to horse sires in 1898 by the mothers of 

 the hybrids of 1897, show no featiu-es that can be 

 traced to the zebra sire; the first (p. Ixxii.) 

 resembles its skewbald Iceland mother, inbred 

 and, therefore, prepotent; the second (p. Ixxv.) 

 takes after its father, its other parent not being 

 inbred ; while the third, though for a few months 

 showing indications of such stripes (p. Ixxvi.) as 

 occur in young horses, differs in no way from 

 the generality of pure-bred foals. 



The word ' prepotent ' was vised just above, and 

 it should be mentioned that (p. xl.-xli)'prepotency 

 may have a great effect in siich experiments ; and, 

 indeed. Professor Ewart suggests it may have 

 been such a factor in evolution as Romanes 



