142 D. J. SCOURFIELD ON HYDRA AND SURFACE-FILM OF WATER. 



Fig. 4. Diagram to illustrate how a weighted match can be 

 supported by the surface-film if tipped with vaseline. 



Fig. 5. Gelatinous material from the basal disc of a Hydra, 

 drawn out into a long thread by being attached to a 

 large air-bubble in a live-box. A small bubble is 

 entangled in the main mass of the jelly. 



Fig. 6. A Hydra vulgaris suspended in the water at some 

 distance below the surface-film. Probably supported 

 by a very delicate thread, as indicated. 



Journ. Quekett Microscopical Club, Ser. 2, Vol. VIII., No. 49, Noveniber 1901. 



