i8o 



THE CHICAGO ACADEMY OF SCIENCES. 



are represented by a single species, and this species has as yet 

 been detected only at Milwaukee, although it is quite possible 

 that it may yet be found within the Chicago area. 



PROPARIA 



33 Phacops 



FIGURE 16. Cephala of Proparia. 24, Placo-paria; 25, Encrinurus; 

 26, Calymene; 27, Diplcura; 28, Cheirurus; 29, 30, Dalmanites; 31, Chas- 

 ; yi.Acaste; ^Phacops. (After Beecher.) 



