Bui. U. S. B. F. 1907. 



PLATE IV. 



FIG. I. WATER GLASS DESIGNED BY THE WRITER TO BE USED FOR OBSERVATION OR 

 PHOTOGRAPHY OF OBJECTS UNDER WATER. 



The cover is shown at the left. 



FIG. 2. TWO-FOOT WATER GLASS SUPPORTED ON FOUR LEGS AND PROVIDED 

 WITH SCREEN, AS USED FOR STUDYING AND PHOTOGRAPHING LAMPREYS 

 (LAMPETRA WILDERI). 



