638 



SCIENCE. 



[N. S. Vol. XIV. No. 356. 



termination of the characters of the offspring 

 and if interbreeding be performed with 

 animals lacking in vigor or with too closely 

 related individuals, it leads to what may be 

 termed degeneration, fehe offspring being 

 frequently delicate, of impaired fertility 

 and, what is remarkable, frequently either 

 entirely or nearly white. 



In connection with the question of inter- 

 crossing Professor Ewart considered the 

 swamping effect upon new varieties, point- 

 ing out how important the decision of this 

 point is upon the validity of the doctrine 

 of natural selection. Darwin himself no- 

 where suggests how new varieties escape 

 swamping, although Wagner by his theory 

 of isolation, and Romanes by that of phys- 

 iological selection, have indicated special 

 methods by which it may be avoided. It 

 seems certain, however, that new varieties 

 make their appearance even in the absence 

 of such barriers to intercrossing, and Pro- 

 fessor Ewart points out that it does not 

 seem to have occurred to biologists that a 

 new variety may be sufficiently vigorous or 

 prepotent to swamp the old, since it is un- 

 questionable that the vigor of the parents 

 has much to do with the character of the 

 offspring. Professor Ewart possesses a 

 skewbald Iceland pony which produces 

 richly striped hybrids to a zebra, but to 

 whole-colored bay, Arab, or Shetland ponies 

 invariably gives offspring colored exactly 

 like herself. So too, black Galloway bulls 

 frequently produce, through long- horned, 

 brightly colored Highland heifers, offspring 

 which would readily pass for pure Gallo- 

 ways, and it is known that the wolf is pre- 

 potent over the dog and the wild rabbit, rat 

 and mouse over their tame relatives. Grant- 

 ing, therefore, a variety more vigorous than 

 the ancestral form, intercrossing, instead of 

 swamping it, would only increase the num- 

 ber of individuals representing it, even with- 

 out any such barriers as are demanded by 

 the theories of Wagner and Romanes. 



6. Maternal impressions. There is no 

 evidence to show that such impressions 

 affect in any way the offspring. 



7. Needs'of the organism. 



8. Direct action of the environment and 

 use-inheritance. Neither of these causes 

 is believed by Professor Ewart to have 

 any action in the production of definite 

 variations. 



9. Telegony or infection. Referring to 

 the celebrated case of supposed telegony 

 described by Lord Morton, the author pro- 

 duced evidence showing that the observed 

 case was more probably due to reversion 

 than to infection, and furthermore he added 

 to his original observations on the subject 

 by stating that since 1895 twelve mares, 

 after producing sixteen zebra hybrids, have 

 given birth to twenty-two pure-bred foals, 

 in none of which is there any indication 

 of the action of telegon3^ It was also 

 pointed out that the observations of Baron 

 de Parana in Brazil upon the pure-bred 

 offspring of mares previously mated with 

 zebras, as well as his results obtained from 

 several mule-breeding establishments which 

 are in reality carrying on telegony experi- 

 ments on a large scale, were entirely neg- 

 ative. 



The address concluded with a brief ap- 

 peal for the establishment of a well- equip- 

 ped institute for biological experimentation 

 on a large scale. 



The address of the President was followed 

 by the report of the special committees ap- 

 pointed at the last meeting of the Associa- 

 tion. That on bird migration in Great 

 Britain dealt with the migration of larks 

 and swallows, while progress was reported 

 by the committee on the Index Animalium, 

 the Natural History and Ethnography of 

 the Malay Peninsula, the coral reefs of the 

 Indian regions and the Zoology of the Sand- 

 wich Islands. 



Of the special papers presented it must 

 suffice to mention but a few. Mr. J. Stan- 



