18. Pectorosus, Con. perdix, 
19..Personatus, ~~ Say, ~eapillaris, _ 
ventricosus, 
20. Purpuratus, Lam. ater, 
| lugubris, 
21. Trabalis, Con. Troostensis, 
22. Ruber, Raf. pyramidatus, 
23.Raveneli, Con. ; saeua asi 3 
24. Retusus, Lam. Lea, torsus, 
rotundatus, 
25. Suborbiculatus, Lam. Lea, glebulus, 
subglobosus, 
26. Subrostratus, Say, iris, 
27. Tetralasmus, Say, 
28. Truncatus, Raf. elegans, 

