PLATE VII. OstTRAcODA. 
1. Hipponicharion Eos, Matt. Mag. ¢ a. Right (?) valve, seen from 
above b. Transverse section near the hinge ——e. Longitudinal 
section of same. From Div. 1, b, 1, Hanford Brook. See p. 132. 
2. Hipponicharion cavatum, Matt. Mag. 4 a. Left (?) valve, seen from 
above —— b. Transverse section near the hinge. From Div. 1, d, J, 
Hanford Brook. See p. 133. 
3. Hipponicharion minus, Matt. Mag. $ —— a. Left (?) valve, seen from 
above b. Transverse section near the hinge. From Div. 1, }, 3, 
Hanford Brook. Seep. 133. , 
4. Beyrichona papilio, Matt. Mag. ¢ a. Both valves spread out —— 0). 
Section near the posterior end ——e. Transverse section of vave near 
the hinge. From Div. 1, b, 4, Hanford Brook. See p. 134. 
5. Beyrichona triangula, n. sp. Mag. +} From Div. 1, b, 3, also in 1, b, 2, 
Hanford Brook. See p. 135. 
6. Beyrichona tinea, Matt. ¢ a. Left valve, seen from above b. 
Transverse section near the hinge line e. Longitudinal section. 
From Div. 1, 6, 4, Hanford Brook. See p. 134. 
7. Beyrichona planata, n. sp. Mag. . Right valve. From Div. 1, b, 2, Han- 
ford Brook. See p. 134. 
8. Beyrichona ovata, n. sp. Mag. ¢. Left (?) valve. From Div. 1, }, 2, Han- 
ford Brook. See p. 135. 
9. Beyrichona rotundata, n. sp. Mag. }. Left valve. From Div. 1, }, 2, 
Hanford Brook. See p. 136. 
10. Schmidtella cambrica, n. sp. Mag. $. Left (?) valve. From Div. 1, d, 3, 
Hanford Brook. See p. 137. 
11. Aparchites secunda, n. sp. Mag. ¢ a. Left valve —— b. The two 
valves seen from the ventral side. From Div. 1, }, 3, Hanford Brook. 
See p. 136. 
