206 
ACTIXOPTERYGII. 
Form. Sf Log. Bathonian: Oxfordshire, Wiltshire, and North¬ 
amptonshire ; (?) S. Bartolomeo, Verona, Italy. 
P. 1640. Vomerine dentition figured in Proc. Geol. Assoc, vol. xi. 
pi. iii. fig. 20 ; Stonesfield Slate, Stonesfield. 
Egerton Coll. 
P. 1646. More imperfect large specimen ; Stonesfield. 
Egerton Coll 
P. 525. Fragment of similar dentition, the undescribed type 
specimen of Pycnodus obtusus, Agassiz, figured in Proc. 
Geol. Assoc, vol. xi. pi. iii. fig. 22; Stonesfield. 
Egerton Coll. 
P. 3739. Portion of smaller vomerine dentition; Forest Marble, 
Atford, near Bath. Enniskillen Coll. 
P. 1647. Portion of still smaller specimen; Stonesfield. 
Egerton Coll. 
39776. Small vomerine dentition, the teeth more closely arranged 
than usual; Stonesfield. Purchased , 1862. 
47982. Vomerine dentition 0*018 in length ; Stonesfield. 
Presented by the Hon. Robert Marsham , 1877. 
P. 3733. Smaller specimen; Stonesfield. Enniskillen Coll. 
P. 3732. Left splenial dentition, the type specimen of Pycnodus 
didymus, described and figured by Agassiz, loc. cit .; 
Stonesfield. Enniskillen Coll. 
P. 3736. Similar specimen, fractured and in counterpart; Stones¬ 
field. Enniskillen Coll. 
P. 1641. Slightly smaller right splenial dentition, showing only the 
bases of the teeth ; Stonesfield. Egerton Coll. 
P. 1649, P. 1666 a, b. Five small examples of the splenial dentition, 
one in counterpart; Stonesfield. Egerton Coll. 
P. 1652. Imperfect left splenial dentition apparently of this species, 
labelled “ Pycnodus Hugii , Ag.,” by Agassiz ; Stonesfield. 
Egerton Coll. 
The following scales are referable either to this or to the preceding 
species :— 
P. 520, P. 3776-77. Type specimens of the so-called Gyrodus per- 
latus, Agassiz (Poiss. Foss. vol. ii. pt. ii. 1844, p. 236), 
