PLATE XXXIV 

 TORNOCERAS (Pages 437-439) 



Figure 1. — rrotoconcli ; showing first septum with lateral edges 

 broken. X 18. 



Figure 2. — Side view of preceding, x 18. 



Figure 3. — Ventral view of protoconcli with one attached air-cham- 

 ber; showing siphonal civcum. X 18. 



Figure 4. — Side view of first whorl. X 18. 



Figure 5. — Ventral view of preceding; sliowing development of 

 ventral lobe. X 18. 



Figure 6. — Transverse section of two whorls near the proto- 

 conch. X 18. 



Figure 7. — Ventral .side of protoconcli, retaining the shell. X 18. 



Figure 8. — Ventral side of .specimen with fir.st cliamber; sliowingsur- 

 face ornaments and indication of siphonal cajcitm. X 18. 



Fkjure 9. — Profile of same. X 18. 



Figure 10. — Surface ornaments on a specimen consisting of a single 

 wliorl. X 18. 



FuiUKE 11. — Four striaj from the second wliorl of a specimen; show- 

 ing funnel sinus. X 18. 



Figure 12. — Vertical section ; showing septa and air-chambers. X 18. 



Figure 13. — Outline of a half-grown specimen, x 3. 



Figure 14. — A series of developed septa beginning with the first ; 

 showing gradual inception and formation of lobes and saddles to the 

 adult period represented hy j. a, b, c, d, represent the 1st, 2d, od, and 

 4th septa, while e and /represent the 7th and 8lh, respectively. X 9. 



Specimens in Yale University Mu-scum, from the Hamilton Shales of 

 AVende Station, New York, except specimen figure 13, which is from 

 IS-Mile Creek, New York. 



