ORDOVICIAN BRACHIOPODA 63 



Dorsal interior with cardinalia consisting of a simple cardinal process and widely 

 divergent brachiophores extending forwards for an average of 17% (range 14% to 

 19%) of the length of 4 pedicle valves and supported by a shallow notothyrial plat- 

 form ; dorsal adductor scars subtriangular, deeply impressed posteriorly on either 

 side of a short low median ridge, and extending forwards for 46% (range 42% to 

 51%) of the length of 4 brachial valves. 



Type material. 



length width (mm) 



Holotype Internal and external moulds of brachial valve 



(BB 35381a, b) 6-5 7-5 



Paratypes Internal and external moulds of pedicle valve 



(BB 35382a, b) n-5 14-0 



Internal and external moulds of pedicle valve 



(BB 35383a, b) 7-5 



Internal and external moulds of brachial valve 



(BB 35384a, b) 8-o 



Internal mould of brachial valve (BB 35385) 7-2 - 



Internal mould of pedicle valve (BB 35386) 7-5 - 



External and internal moulds of brachial valve 



(BB 35402a, b) 7-0 



External and internal moulds of pedicle valve 



(BB 35403a, b) 7-0 



Horizon and localities. Whittery Shales : BB 35384 from outcrops in stream 

 at north end of Spring Coppice, 865 yds south-east of Hockleton Bridge (Grid Ref. 

 SO 279997) ; all other specimens from Whittery Quarry at the south end of Whittery 

 Wood, near Chirbury (Grid Ref. SO 275981). 



Discussion. The sample of Whittardia paradoxica available for assessing the 

 morphological variation within the species was too small to estimate proportional 

 growth, but statistics incorporated in the description were calculated for valves 

 between 3 and 12-4 mm in length and give some idea of the variability. 



Family DOLERORTHIDAE Opik 1934 



Subfamily DOLERORTHINAE Opik 1934 



DOLERORTHIS Schuchert & Cooper 1931 



Dolerorthis cf. tenuicostata Williams 



(PL 10, figs. 3, 5, 7, 10, 13) 



I 955 Dolerorthis tenuicostata Williams in Whittington & Williams : 406. 



The incomplete external and internal moulds of a brachial and pedicle valve 

 (BB 35459a, b ; BB 35460a, b) of Dolerorthis have been collected from the Whittery 

 Shales exposed in Whittery Quarry in the south end of Whittery Wood, near 

 Chirbury (Grid Ref. SO 275981). The shell was ventri-biconvex with a pedicle 

 valve about one-fifth as deep as long, sloping evenly away from the beak, and a very 



