PYCNODOinTDiE. 
229 
P. 1650, P. 3748. Eight and left splenial dentition, of small size; 
Corallian, Lindnerberg, Hanover. 
Egerton and Enniskillen Colls. 
30871. Left splenial dentition, probably of this species, shown of 
the natural size in PL XYII. fig. 3 ; Portland Stone, 
Weymouth. Purchased , 1856. 
Microdon minutus (Munster). 
1846. Pycnodus minutus, G. von Munster, Beitr. Petrefakt. pt. vii. 
p. 41, pi. iii. fig. 7. 
1875. Microdon minutus , K. Fricke, Palseontogr. vol. xxii. p. 369, pi. xx. 
figs. 5-9. 
Type. Fragment of mandibular dentition ; Palaeontological 
Museum, Munich. 
A species of moderate size, known only by the dentition. On the 
vomer [according to Fricke] the teeth of the principal series much 
transversely elongated, comparatively closely arranged; those of 
the inner paired series minute or aborted ; those of the outer paired 
series small and irregularly rounded. Splenial teeth closely arranged ; 
those of the principal series at least twice as broad as long: those 
of the innermost series round and minute ; those of the inner 
flanking series much transversely elongated, relatively large, and 
those of the outer flanking series smaller, either round or slightly 
elongated transversely. 
Form. Sf Loc. Kimmeridgian : Hanover; Switzerland. 
P. 3747. Left splenial dentition; Lindnerberg, Hanover. 
Enniskillen Coll. 
P. 3746 a. Portion of larger right splenial dentition; Soleure, 
Switzerland. Enniskillen Coll. 
Microdon quincuncialis (Blake). 
1875. Pycnodus quincuncialis, J. F. Blake, Quart. Journ. Geol. Soc. 
vol. xxxi. p. 223. 
1880. Pycnodus quincuncialis , E. Damon, Geol. Weymouth, ed. 2, 
Suppl. pi. xi. fig. 10. 
1890. Microdon quincuncialis, Woodward & Sherborn, Catal. Brit. 
Foss. Yertebrata, p. 122. 
Type. Yomerine dentition ; British Museum. 
A species of large size. Inner vomerine teeth sparsely arranged, 
those of the principal series not much broader than long, and the 
paired teeth very irregular in size and form, with few supplementary 
