CESTRACI0XTIDJ2. 
303 
41400. Larger distal portion of a dorsal fin-spine, showing the 
posterior denticles less clearly divided into two series 
above than below; Lower Kimmeridge Clay, near 'Wey¬ 
mouth, Dorsetshire. Purchased , 1869. 
P. 155. Imperfect spine, figured in Damon’s 4 Geol. of Weymouth,’ 
Append, pi. x. fig. 4; near Weymouth. The bases of 
the lower posterior denticles are seen distinctly separated 
into two series; and the form of the transverse section 
of the upper part of the fragment is altered by the 
breaking away of the anterior margin. Purchased , 1881. 
41177, 41222, 41399. Fragments of larger spines, with more 
, numerous lateral longitudinal ridges; near Weymouth. 
One specimen shows three irregular series of posterior 
denticles. Purchased , 1868-69. 
46335. Portions of a spine closely resembling the type specimen of 
Hybodus acutus in size and characters; Kimmeridge Clay, 
Foxhangers, near Devizes, Wiltshire. Cunnington Coll. 
(b) Cephalic Spine. 
41876. Exserted portion of spine; near Weymouth. 
Purchased , 1869. 
VI. Purbeck. —The following specimens were all obtained from the 
neighbourhood of Swanage, Dorsetshire. 
(a) Dorsal Fin-spines. 
33476. Two spines indistinguishable from E. dorsalis , Agass., of 
the Stonesfield Slate. Purchased , 1858. 
35569. A less perfect similar spine. Purchased , 1859. 
44847 a. Fragment of a more curved spine,-nearly similar. 
Presented by Benjamin Bright , Esq., 1873. 
21348, 24725. A larger more robust spine, and a portion of another. 
Purchased, 1847, 1849. 
46908. Similar spine, nearly complete, but wanting posterior den¬ 
ticles. Purchased , 1875. 
21347-8. Two imperfect crushed spines of the form named Hybodus 
strictus , Agassiz l . Purchased , 1847. 
21974. Two imperfect similar spines. Purchased , 1848. 
1 Poiss. Foss. vol. iii. (1837), p. 45, pi. x. figs. 7-9. 
