TEE CARBONIFEROUS LIMESTONE OP SOUTH-WEST GOWER 49 
interspersed with Bryozoa. Spines of Productus semire- 
ticulatus are numerous, but I found no specimens of the 
entire shell. 
The Brachiopods are represented, however, by a gigan- 
tic Productus, one specimen of which measured 15 inches 
across the hinge line. 
The other fossils collected from this sub -zone were Cono- 
cardium sp., Conocardium, cf. aliforme, Orthotetes crenistria 
(mut. S.), Seminula ficoidea, Spiriferina cf. laminosa, 
Chonctes papilionacea, Chonetes cf . hardrensis (rare), Rhipi- 
domella af£. Michelini, the Corals Caninia cylindrica (mut. 
S^), the Bryozoa Glauconome gracilis, and Heterotrypa 
tumida, and the Trilobite Phillipsia pustulosa. 
Chonetes cf. hardrensis and Rhipidomella aff. Michelini 
occur only at the base of the series. 
The last Gastropod Bed (V) occurs 50 feet below the 
lowest shale. Loxonema and Platyschisma are still com- 
mon, but Dentalium was not found ; Bellerophon, on the 
contrary, rare in Gastropod Bed (I), grows more and more 
abundant as one passes downward to Bed (V.). 
I have described these Gastropod Beds in detail, as 
they are persistent through the entire breadth of the 
Gower Peninsula, and crop out near Parkmill on the East 
Coast, with precisely the same characteristics as are seen 
at Overton. 
The last bed of Sub-zone consists of over 150 
feet of hard blue limestone (14), with vast numbers of 
broken crinoid stems and scattered colonies of Syringopora 
and Lithostrotion Martini and a few specimens of Bellero- 
phon. The exact thickness of this last bed cannot be 
stated, as it passes down below low water mark. 
The upper beds of Sub-zone are palaeonto- 
logically the most interesting in the Gower series. In the 
number and variety of their fossils they exceed any of the 
other beds, and the 90 foot layer of limestone and shale is 
E 
