TPAD ANAND) OXON. 87 
LINGULELLA AUGA (Walcott) (p. 480). 
Fieures 6 and 6a. Casts in shaly limestone of interior of two ventral valves. U.S. Nat. Mus. Cat. Nos. 27306a and 
27306b, respectively. 
6b. Cast of the posterior portion of the interior of a distorted ventral valve, the type specimen. U.S. Nat. 
Mus. Cat. No. 27306c. 
6c. Cast of the posterior portion of the interior of a ventral valve, showing a trace of the visceral area. U.S. 
Nat. Mus. Cat. No. 27306d. 
6d and 6e. Casts of the interior of two dorsal valves. U.S. Nat. Mus. Cat. Nos. 27306e and 27306f 
respectively. 
The specimens illustrated by figures 6, 6a-e are from Locality 10a, Middle Cambrian shaly sandstones at Shooks 
Gap, 10 miles southeast of Knoxville, Tennessee. 
Fieures 6f and 6g. Ventral and dorsal valves from Locality 10b, a siliceous limestone interbedded in the Middle 
Cambrian shaly sandstones at Shooks Gap, 10 miles southeast of Knoxville, Tennessee. The outer 
surface with strong concentric striz is finely preserved. U.S. Nat. Mus. Cat. Nos. 27306g and 27306h, 
respectively. 
LINGULELLA TUMIDA Matthew (p. 537). 
Figure 7. Exterior of ventral valve from Locality 18i, Middle Cambrian sandy shales on Gillis Brook, Cape Breton, 
Nova Scotia. U.S. Nat. Mus. Cat. No. 51769a. 
7a. Cast of the interior of a ventral valve associated with the shell represented by figure 7, showing the high 
area and strong vascular sinuses. U.S. Nat. Mus. Cat. No. 51769b. 
7b. Cast of the interior of a ventral valve from Locality 18r, a little different horizon from that represented 
by Locality 138i, Middle Cambrian sandy shales on Gillis Brook, Cape Breton, Nova Scotia. U.S. 
Nat. Mus. Cat. No. 57011a. 
7c. Exterior of ventral valve associated with the shell represented by figure 7. U.S. Nat. Mus. Cat. No. 
51769c. : 
7d. Cast of the interior of a ventral valve associated with the shell represented by figure 7b, retaining a 
portion of the shell on the umbo. U.S. Nat. Mus. Cat. No. 57011b. 
