ANIMAL PRODUCTION. 377 



rufous, or leather-dun, so it may be assumed that the remote ancestors of 

 the modern zebras only differed in their coat color from Prejvalsky's horse 

 in being moi'e richly striped. It is also stated that there are 2 kinds of 

 duns, first, those without either a dorsal band, shoulder or leg stripes, and, 

 second, those with the band and as a rule with more or less distinct bars 

 on the legs. 



" Yellow-duns with a dorsal band and at least vestiges of leg bars are in 

 all probability either the desceudauts of a long line of dun ancestors or are 

 reversions. . . . That dun is latent in some bays and blacks was proved 

 recently by a black Shetland mare from Unst producing to a bay Arab (lusaf), 

 with a dorsal band and leg bars, a richly striped yellow-dun." 



"A light chestnut Iceland pony mare in my stud produced a bay-dun with 

 dark points to a yellow-dun Prejvalsky stallion, and a richly striped yellow- 

 dun Highland mare produced first a dark bay with dark points and then a 

 light bay (also with dark points) to a chestnut thoroughbred (Diplomat). 

 I am, hence, not surprised that Lord Morton's chestnut Arab produced a filly 

 of a bay or bay-dun color to a quagga." 



" My crossing experiments do not support the view that chestnut never 

 contains bay or that yellow-dun is always dominant with chestnut, bay, brown, 

 and black. They, on the whole, support the view that characters are ' patent ' 

 or 'latent' rather than, as Mendelians say, 'present' or 'absent.'" 



Lord Morton's quag'ga hybrid and origin of dun horses, J. Wilson and 

 J. C. EwART {Nature [London], 8Jf (1910), No. 2138, pfi. J,9J,, 7/95).— A further 

 discussion in support of the contentious noted above. 



The inheritance of dun coat color in the horse, J. B. Robertson {Yet. Rec, 

 23 {1910), No. 1161, pp. 225-22S) .—Data were obtained from Weatherby's 

 studbook and the early Racing Calendars with reference to the dominance of 

 dun, but are not sufBcient from which to draw definite conclusions. 



History and peculiarities of the mule-foot hog% W. J. Spillaian {Amer, 

 Breeders Mag-, 1 {1910), No. 3, pp. 178-182, figs. 3).— This contains further 

 details concerning the history and characteristics of this breed (E. S. R., 22, 

 p. 379). 



Investigations on the origin and historical development of the bulldog 

 and pug-faced animals, B. Poetting {Untersuchungen ilher die Entstehimg und 

 die historische Entwicklung der Bulldogge und des Mopses, Inaug. Diss., Univ. 

 Bern, 1909, pp. 33, pis. 7; rev. in Arch. Rasscn u. Gesell. Biol., 7 {1910), No. 4, 

 pp. 498, 499). — The author finds that under domestication there is a tendency 

 for the facial parts of all domesticated animals to become shortened because 

 the teeth are used less than when in a wild state, where any tendency of this 

 kind would not survive long enough for the individual to breed. The changes 

 in the teeth and other portions of the skull correlated with short-headeduess are 

 discussed. 



Report of committee on animal hybrids, W. J. Spillman et al. {Amer. 

 Breeders Mag., 1 {1910), No. 3, pp. 193-196).— This contains an account of the 

 work in animal hybridization now in progress at the experiment stations and 

 elsewhere in the United States. 



Problems of animal morphology, G. C. Bourne {Science, n. ser., 32 {1910), 

 No, 830, pp. 729-7/(2).— An address before the zoological section of the British 

 Association for the Advancement of Science in 1910. 



It is pointed out that in the past the study of animal form has placed the 

 evolutionary theoi-y on a sound basis, but that if morphology is to advance in 

 the future the work must be so broadened as to study the causes which produce 

 changes in the animal body. The ground is taken that investigations show that 

 external conditions modify the germ cell and that such modifications are 



