660 



SCIENCE 



[N. 8. Vol. XXVI. No. 672 



chemical conceptions that, in all the range 

 of characters with which we, breeders, 

 have dealt, no phenomenon suggestive of 

 valency between characters has been ob- 

 served. Everywhere we meet the fact that 

 on an average the number of germ cells in 

 which our allelomorphs are present is the 

 same as the number in which these allelo- 

 morphs are absent. Whatever the kind of 

 characters concerned, equality of number 

 is the rule. While, therefore, we see very 

 readily that the operations of the allelo- 

 morphs are due to chemical action, allelo- 

 morphism itself can not be expected to 

 prove a chemical phenomenon in any 

 simple sense. Allelomorphism is rather to 

 be compared to the separation of sub- 

 stances which will not mix, and it is not 

 impossible then in some of our more com- 

 plex cases we are concerned with various 

 phenomena of imperfect mixture. The 

 elucidation of this part of the subject must 

 be left to the physicist. 



I can not conclude without expressing 

 something of the delight which I feel that 

 biologists are at length devoting them- 

 selves in good earnest to genetic problems. 



To those whose memories go back even 

 to the International Congress of 1898 in 

 Cambridge the change is indeed amazing. 

 Then we spoke little of genetics— little, 

 that is to say aloud, or in official pro- 

 grams, though under our breath some of 

 us were murmuring of these things. In 

 this congress the voices that we dared not 

 raise in 1898 are rather in danger of 

 hoarseness from too much speaking. But, 

 seriously, we students of genetics may 

 look forward to the future with great 

 confidence and hope. Those who next 

 week will see Professor Davenport's 

 magnificent institution at Cold Spring 

 Harbor will appreciate that a wonderful 

 and most hopeful beginning has been 

 made. The work of Professor Davenport 



and his staff, of Professor Castle, at 

 Harvard, of Professor Tower, at Chicago, 

 and of others I might name, are all evi- 

 dences that a great and combined advance 

 has begun. We in Europe will bear our 

 part also, and if we have not any very fine 

 equipment we must console ourselves with 

 the thought that light-armed troops may 

 move the faster for a while. With their 

 base on Cold Spring Harbor, or Woods 

 Hole and the Biologische Versuchsanstalt 

 in Vienna, the allied armies of genetics, 

 cytology and experimental zoology they 

 start for the grand attack; and I think 

 when we meet at the end of another period 

 of ten years, there will be victories to 

 record. William Bateson 



Cambkidge Univeksitt 



SCIENTIFIC BOOKS 



Resuliats du Voyage du S. Y. Belgica en 

 1897-9, sous the commandement de A. de 

 Gerlache de Gomery. Rapports Scientif- 

 iques. Zoologie. Injects par G. Severin 

 (and twenty others), 92 pp., 4°, V. pL, 1906; 

 Ostracoden von G. W. Muller, 8 pp., I. pi., 

 1906 ; Holothuries par E. Heeouard^ 1Y pp., 

 n. pi., 1906; Medusen von Otto Maas, 32, 

 pp., III. pL, 1906. 



A f resli batch of the valuable reports of the 

 Belgian Antarctic Expedition have come to 

 hand, the printing and illustrations of the 

 elegance which has characterized the series. 



The number of insects which have been 

 brought back from the Antarctic remains 

 pitiably small, and in marked contrast with 

 the richness of the Arctic regions. Besides the 

 Collembola taken in the Gerlache channel, a 

 Podurella and pedicularian obtained by the 

 Southern Cross, no insect is known except a 

 Chironomid fly of the new genus Belgica, and 

 the larva of perhaps another species of the 

 same family. These minute creatures, whose 

 wings are so reduced that they are incapable 

 of flight, are found in the vicinity of small 

 pools of water where the seabirds roost on the 

 rare bits of bare ground or rock which are 

 exposed along Gerlache Channel. 



