THE CARBONIFEROUS LIMESTONE OF SOUTH-WEST GOWER 55 
Productus semireticulatus (mut. Si) 
Orthotetes crenistria (mut. S.) 
Spiriferina cf. laminosa 
Caninia cylindrica (mut. Si) 
Indicate the 
survival of 
the Tournai- 
sian fauna. 
Ghonetes cf. hardrensis 1 Occur near 
Rhipidomella aff. Michelini f the base. 
A new species of the punciatus group of Prod-ucti is 
apparently very common at Overton ; this species has 
already been found by Mr. T. F. Sibly in at 
Weston. Heterophyllia sp. is the first record of this genus 
from South Wales or South-West England. Gastropods 
and Bryozoans are abundant, and Trilobites are not un- 
common ; the species appear to be the same as those found 
in the Avon Section, Bristol, but the Gastropods are 
certainly more numerous. Among the Bryozoans, Hetero- 
try pa iumida is very characteristic, as it is in the Avon 
Section. 
UPPER SEMINULA ZONE, S^. 
Forming the upper part of the Overton Section and the 
lower part of the Porteynon Section. 
Fauna — 
Productus aif. Cora (mut. S. 2 ) (abundant). 
Productus hemisphericus (abundant). 
Seminula ambigua (mut. S. 2 ). 
Seminula aff. ficoidea. 
Athyris sp (cf. glahristria). 
Athyris planosulcata) 
[ occur near base. 
Alveolites sp. j 
Syringopora cf. distans, 
Lithostrotion Martini. 
Lithrostrotion a^ne. 
Carcinophyllum 0. 
