NATURAL SCIENCES OF PHILADELPHIA. 243 



p. 180, line 13, for 5 read 8. 



p. 191, line 5 from bottom, for Colkett read Calkins. 



p. 165, line 19, Z. cerinoideus. Jaw as usual. Teeth 34 — 1 — 34, with 9 perfect 

 laterals. Charleston, S. C. (W. G. Masyck.) 



p. 171. Note. Z. cerinoideus also has these characteristics of Zonites. 



p. 176, line 15, add : excepting in the absence of the peculiar inner side cutting 

 point of that species. 



p. 186. Ccecilianella. Since the above was printed, I have had an opportunity, 

 thanks to Mr. Bland, of examining the jaw and lingual membrane of C. Gundlachi 

 of St. Martin. The jaw has decided, numerous, broad, flat, slightly separated ribs, 

 denticulating either margin. 



In the plates the inner cutting point should have been bifid in pi. X. fig. 1, 16th 

 tooth. (The fourth figure from the right is the 10th tooth.) Fig. 3, d. PI. XI. fig. 

 1, h. Pi. XII. fig. 1, 31st tooth. 



Helix ruficincta, pi. XIV. fig. 3. Another membrane has cutting points on all the 

 laterals. 



Helix exoleta. Two of four membranes recently examined have side cutting points 

 to outer laterals; the inner cutting point of marginals are also bifid. 



