474 Messrs. R. Etheridge, Jun., and A. H. Foord on 
the characteristic fossils of that formation. In some speci- 
mens the mural pores have been filled with chalcedony of a 
concentric structure. It may be noted that the pores are so 
large as to be seen on a polished surface with a hand-lens. 
Locality and Horizon. Dudley, Wenlock Limestone. 
Collection. British Museum (Natural History), and A. H. 
Foord. 
Genus CH&TETES, Fischer, 1837. 
Cheetetes Lonsdalet, Eth. & Foord. (Pl. XVII. figs. 2-2 ¢.) 
Sp. char. Corallum incrusting in the young state, pro- 
bably forming large masses in a more advanced stage of 
growth, of undeterminable dimensions, composed of minute 
closely contiguous corallites, of which three or four, according 
as they are measured in conformity with their longer or shorter 
diameter, occupy the space of 1 millim. Calices polygonal, 
very irregular in outline, with from one to four tooth-like 
projections characteristic of Chetetes. 'Tabule numerous, 
complete, horizontal, or slightly arched, usually about one 
tube-diameter apart. 
Obs. So far as we are’ aware, no species of Chetetes has 
been described hitherto from the Devonian rocks of Devon- 
shire, as the Chwtetes tumidus mentioned by Mr. T. M. Hall 
from the Pilton beds of Braunton (Quart. Journ. Geol. Soe. 
1861, xxii. p. 376), if correctly determined, is now known to 
be a Monticuliporid. We have the present species in the 
young state incrusting a Cyathophylloid coral, and there is 
evidence to show that at a more advanced age it became 
massive and probably lobate. The largest specimen, which 
is a polished fragment, measures 83 centim. in its greatest, 
by about 6 centim. in its smallest diameter. This species is 
distinguished from all others known to the writers, except 
C. depressa, Fleming, sp., by the minuteness of its corallites, 
and from the latter by the numerous septum-like projections of 
its calices and the greater irregularity of the corallites. The 
so-called “septal teeth”? in Chetetes are now known to be 
due, as originally pointed out by Lonsdale, to “ fission taking 
place in the older corallites”? (wide Journ. Linn. Soe. vol. 
xiil., Nich. & Eth., jun., “On the Genus Alveolites,” &c. 
p- 853, 1877). It becomes therefore a question whether such 
a character can be used as a means of specific separation, 
unless, indeed, the degree of fissiparity differs in various species. 
Under the circumstances it will be better to say that the 
form now before us differs from its nearest ally CU. depressa, 
Flem., sp., in the greater irregularity of its corallites. 
