THE CARBONIFEROUS LIMESTONE OF BURRING TON COMBE 25 
(ii) Resupinata sub-zone. 
Special faunal characters — 
Brachiopods, 
Cliothyris glahristria attains its maximum and is 
associated, though rarely, with Schizophoria resupinata. 
Spirifer aff. clathratus and var., though less abundant 
than in the clathratus sub -zone, are very common through- 
out. 
Syringothyris cuspidata, in the typical form characteristic 
of the Syringothyris Zone, occurs at the top of this sub-zone. 
Syringothyris aff. laminosa enters at the base, and is 
abundant at a certain level. 
Chonetes cf. hardrensis is common at various levels 
throughout this sub-zone, and is associated with Chonetes 
aff. papilionacea in the upper part. Chonetes papilionacea 
enters, and is very common in the upper part of the sub- 
zone. 
Productus cf . Martini is replaced by a larger form closely 
allied to Productus semireticulatus. 
Rhipidomella aff. Michelini occurs, but has passed its 
maximum. 
Orthetetes aff. crenistria occurs abundantly throughout. 
Corals. 
Zaphrentis aff. Phillipsi and Zaphrentis aff. cornuco- 
piae become abundant at the top of the sub -zone. 
Caninia cylindrica enters in the lower part of the sub- 
zone and rapidly becomes abundant. 
Amplexus cf . coralloides appears early in the sub -zone and 
soon attains a maximum. At its maximum it is abundant. 
Michelinia cf. favosa attains its maximum, being 
very abundant at certain levels. 
Syringopora 0 occurs in abundance. 
Note. — Owing to the very unsatisfactory exposure of the upper 
half of this sub-zone, little is known concerning the relative abun- 
dance of various fossils in the beds underlying Horizon y. The 
