

"•P* ^Sk 7^* "* " * 



r -/"Ifc « ^ _. 



Fig. 1. Light microscope pictures of a, Chlorohydra and b, Pelmatohydra. 

 In a the epidermis is at the top and the gastrodermis at the bottom. The two 

 layers are separated by the mesolamella along which muscle fibers may be 

 seen. In b the epidermis is at the right and the gastrodermis at the left with 

 the mesolamella between. Note the obvious muscle fibers at the base of the 

 epidermis and the connection between epithelia at the circle. Desmosomes 

 appear at the arrows. The black circular objects in the gastrodermis of a 

 are Zoochlorella; in b similar structures are food particles. C, cnidoblasts; 

 N, nucleus, o— 2200X. fc— 2200X. 



53 



