A Simple Apparatus. 



175 



II B and II cultures but still protects against II A cultures. 

 Hence, in terms of the protective substances in chicken serum, 

 Types II A and II B are main groups with Type II as a subgroup 

 to them both. 



Fractionation of the serum by means of ammonium sulphate 

 and dialysis showed that the protective substances adhere quanti- 

 tatively to the water-insoluble globulin. 



86 (1668) 



A simple apparatus for studying the factors influencing fish migra- 

 tion. 



By F. E. CHIDESTER. 



[From the West Virginia University, West Virginia.] 



At the request of Dr. H. M. Smith, commissioner of fisheries, 

 certain studies have been made at the Woods Hole Laboratory of 

 the Bureau of Fisheries on the factors influencing fish migration. 



In testing reactions to various salts a simple apparatus was 

 devised that seems to eliminate some of the drawbacks of the 

 well-known Shelford apparatus. 



Fig. 1. 



It consists (Fig. 1) of two troughs running almost parallel 

 into a large trough which has a movable partition permitting the 



