Fig. 1. Cyprinotus gregarius. 1. 
59 X. 3. Shell, seen from above, 2; 52 X. 
6. Anterior margin of the right valve, seen from within, 9; i. 1. = inner line; j. 1. = line of joining (»Verwachsungslinie>); 
Right valve, seen from the side, 2; 59 X. 2. Left valve, seen from the side, 2; 
4. Shell, seen from above, S;; 52X. 5. Sculpture of the shell, 5; 185 X. 
h. b. = hyaline border (»Saum»); e = edge of the valve; 260 X. 7. Upper lip, 2; fr. str. = frontal stripe; tr. str. = trans- 
versal stripe; 340 X. 8. Second antenna, distal part, seen from outside, somewhat pressed, 9; 520 X. 9. Sensorial 
bristle of the end-joint of this antenna; 900 X. 10. Second antenna, distal part, seen from within, 37; 565 X. 
11. Maxilla, 2; 565 X. 12. A bristle of this extremity; 1265 X. 13 and 14. Furca of one specimen, &; 
e = end of the body; 220 X. 15. and 16. Furca of two other specimens, SS; 220 X. 
