﻿208 DK. A. VAUGHAN ON THE PALiEONTOLOGICAL [May I905, 



Exposure. — The middle part of that portion of the section 

 which lies between Kin grove-Farm Bridge and Lilliput-Farm 

 Bridge. 

 Faunal character: — 



Top of the Tournaisian : C. 

 Zaphrentis is not uncommon in the lower part of (1). 

 Chonetes aff. papilionacea and Orthotetes crenistria, associated 

 together, crowd certain bands near the top of (1), and the 

 last-mentioned fossil passes on into the base of (2). 

 Syringothyris aff. laminosa occurs in considerable numbers, 

 just below (2). 



Base of the Visean : S x . 

 Seminida ficoidea and its variants enter about the middle of 



(3), and from that point become increasingly abundant. 

 Productus 6 (?) * occurs sparingly in (3). 



Both these fossils teem throughout (4). 

 Caninia cylindrica (var. bristolensis) and Lithostrotion Martini 

 enter together at the top of (4), and are there extremely 

 abundant. 

 Syringopora cf. distans is common in the upper part of (4). 

 The zone is considered to end where Caninia dies out. 

 Correlation with the Avon section : — 

 Resemblances : 

 All the fossils which occur at Sodbury enter in precisely the 

 same relative order as they do in the Avon section. 



In both sections : — After Zaphrentis has died out Syringothyris 

 afT. laminosa becomes an important distinctive fossil, and certain 

 beds are crowded with Orthotetes and Chonetes aff. papilionacea. 



Orthotetes ends its long predominance at the same level and, 

 throughout the rest of the Carboniferous Limestone, plays an 

 extremely-minor part. 



Seminula becomes abundant, before giganteid Producti and 

 Lithostrotion Martini are met with in any numbers. 



At the top of the zone Caninia cylindrica var. bristolensis is as 

 abundant at Sodbury as in the Avon section, and is similarly 

 associated with crowds of Lithostrotion Martini, Productus (?), 

 and Seminula, as well as with the same species of Syringopora. 

 Differences: 

 Owing to the absence (or scarcity) of Caninia at the base of the 

 zone, the lower part of the Caninia-Zone (Syringothyris-Zone) 

 appears to be entirely distinct from the upper part (semireticulatus- 

 subzone). In fact, at Sodbury, the palseontological facies of the 

 Lower Carboniferous Limestone (which comprises the zones of 

 Cleistopora, Zaphrentis, and Syringothyris) is so entirely distinct 

 from that of the Seminida-Zone above, that it would seem impos- 

 sible to include the whole series in one system. 



The only genera which bridge the gap at Sodbury are Syringo- 

 pora, Productus, and Orthotetes. The species of Syringopora that 



1 A field-determination, and possibly including Productus aff. hemisphericus. 



