136 MESOZOA. 
3. Professor F. E. Schulze discovered a small marine organism — 
Trichoplax adherens—in the form of a thin, ¢hvee-layered, externally 
ciliated plate ; and Monticelli records a similar form under the title 
Treptoplax adherens. But Trichoplax is now said to be the planula 
of the Hydromedusan Eleuthera, 
4. Professor J. Frenzel discovered. in brine solutions a minute 
Turbellarian-like organism—Salénella salve—whose body consists of 
one layer of cells (Fig. 64). There is an anterior mouth, a ciliated 
food canal, and a posterior anus. The ventral surface is finely ciliated, 
the other cells bear short bristles. The animal reproduces by trans- 
verse fission, but conjugation and encystation also occur. 
It must be confessed that some corroborative evidence in regard to 
this peculiarly simple animal is much to be desired. 
