REVIEWS 127 



the author with a view to proving the fact of reversion, and also to 

 throw light upon the subjects of inbreeding and prepotency. 

 Reversion is regarded more as a negative than a positive influence, 

 and " mainly due to the development being abruptly arrested so as 

 to reproduce a lost ancestor." Instances of reversion in horses are 

 given, including remarks on the teeth, digits, and forearm. One 

 conclusion arrived at from the experiments with regard to pre- 

 potency in the male is that the possession of such a quality may not 

 necessarily make up for any deficiencies in the female. 



In summing up the results of his " telegony " experiments, 

 the Professor states that the evidence in support of undoubted 

 " infection " having ever occurred is most unsatisfactory, and he 

 regards the " reversion " hypothesis as sufficient to account for all 

 the supposed cases of infection. 



Part I. consists of two papers, the first on the Birth of a Hybrid 

 between a Burchell's Zebra and a Mare, the second on Zebra-Horse 

 Hybrids ; Part II. is a discussion on Telegony, with observations 

 on the striping of Zebras and Horses, followed by a section 

 on Reversion in the Equidiz. All the papers are beautifully 

 illustrated. 



Science is much indebted to Prof. Ewart for the interesting, 

 elaborate, and costly experiments that he has so successfully con- 

 ducted at Penycuik. It is these original investigations, mainly, 

 that render the book under consideration so eminently worthy of 

 careful study by the practical breeder, the theoretical evolutionist, 

 and the naturalist alike. 



CONTRIBUTIONS TOWARDS A " CYBELE HIBERNICA " ; BEING OUT- 

 LINES OF THE GEOGRAPHICAL DISTRIBUTION OF PLANTS IN IRELAND. 

 Second Edition. Founded on the papers of the late Alexander 

 Goodman More, F.R.S.E., etc. By Nathaniel Colgan, M.R.I.A., 

 and Reginald W. Scully, F.L.S. (Dublin : Edward Ponsonby, 1898.) 



The flora of Ireland is of very considerable interest to the 

 botanists of Scotland alike in its likenesses and in its unlikenesses to 

 the flora of Scotland. The " Cybele Hibernica " issued in 1866 by 

 the well-known Irish botanists Moore and More has passed out of 

 date (in no small degree owing to the stimulus given by it to a 

 fuller knowledge and research), and a very great deal has been done 

 since its issue to extend what was known as to the geographical 

 distribution of Irish plants. Many systematic investigations have 

 been undertaken, largely under the auspices of the Royal Irish 

 Academy ; and reports on these, and papers in the Irish Naturalist 

 and elsewhere, added much to the records of earlier date. Mr. More 

 hoped to be himself able to prepare and issue a second edition of 

 the " Cybele " ; but this his health did not permit him to accomplish. 

 He left, however, numerous notes prepared for this end, set apart 

 funds to pay the necessary expenses, and named Messrs. Colgan and 



