PLATE XXV. 



PAGE 



Figs. 1, la, 2. Calyptraphokus jacksoni Clark 145 



1. Dorsal vie^w of tyi^e. Sheckels Farm near South Eiver. 

 la. Ventral vie\v of same specimen. 



(Fig's. 1 and la are modified and corrected copies of the original 

 figures in Bull. 141, U. S. Geol. Survey.) 



2. Dorsal view of larg'e individual from same locality. 



Fig. 3. Calyptraphorus teinodifekus Conrad 145 



Dorsal view. 2 miles below Potomac Creek. 



Figs. 4, 4a. Calyptraphorus trinodifervs (?) Conrad var 146 



4. Ventral view. 1 mile southeast of INIason Springs. 

 4a. Dorsal view of the same specimen. 



Figs. 5, 6. Aporrhais potomacensis n. sp 146 



5. Ventral view of imperfect individual. Digitations restored from 



original of Fig. 6. 1 mile northeast of Piseataway. 



6. External view of labrum of large individual from same locality. 



377 



