CESTBACIONIID^. 
313 
Asteracanthus acutns, Agassiz. 
18.37. Aiteracanthus acutus, L. Agassiz, Poiss. loss. vol. iii. p. 3.3, 
pL viii. a. figs. 1-3. 
Type. Distal half of dorsal fin-spine ; Bedford Museum. 
Dorsal fin-spine attaining a length of about 0‘27, much laterally 
compressed; anterior face keeled; posterior face slightly convex, 
with large denticles. Ornamental tubercles relatively large, elon- 
gated, arranged in close series, rarely fused into ribs in known 
specimens. 
The teeth of this species are probably described under the name 
of Strophodus tenuis, Agassiz. 
Form. ^ Loc. Great Oolite : Oxfordshire. Combrash : Northamp- 
tonshire. (?) Forest Marble : Dorsetshire. 
43616. Much abraded but nearly complete spine, originally measuring 
about 0-27 in length ; Stonesfield Slate, Stonesfield, Oxford- 
Purchased, 1872. 
28597. Extremity of spine, with some of the tubercles fused, pro- 
bably of this species ; Stonesfield Slate, Eyeford. 
Purchased, 1853. 
B. 5377. Imperfect exsertod portion of spine ; Great Oolite, Enslow 
Bridge, Oxfordshire. Purchased, 18 <7. 
47131. Incomplete crushed exserted portion of spine ; Cornbrash, 
Botolph’s Bridge, Peterborough. Sharp Coll. 
B- 2853. An imperfect impression of a spine, doubtfully assigned 
to this species, and labelled A. stutchburyi, Aga.ssiz *, by 
the Earl of EnniskiUen ; Forest Marble, near Bridport, 
Dorsetshire. Ennishillen Coll. 
Asteracanthus verrucosus, Egerton. 
1855. Asteracanthus verrucosus, Sir P. Egerton, Fi^. & Descrips. 
Brit. Organic Remains (Mem. Geol. Surv.), dec. xiii. pi. ii* 
Type. Dorsal fin-spine ; Dorchester Museum. 
Dorsal fin-spine attaining a maximum length of about 0*32, 
laterally compressed, not keeled anteriorly ; posterior face slightly 
raised, with two series of large denticles. Ornamental tubercles 
ver)’ numerous, closely arranged, mostly oval in form and disposed 
* This name is given, vrithout definition, to a fossil said to have been derived 
from the Lias of Charmouth, Dorset (Poiss. Foss. voL iii. p. 1(7). 
