THE BEACHIOPODA. 33 



The variety W. carinata with the excavated front margin is so dis- 

 tinct from the ordinary form of the species that I consider it worth 

 naming as a variety, I therefore name it Waldheimia carinata var. 

 crewhernensis. This variety is figured by Mr. Davidson at sup- 

 plement plate xxiii., figure 15, only the excavation of the valves 

 is usually much greater. Young forms of this variety also 

 exhibit the same excavation. 



Dimensions. — W. carinata — Length, 1 6 ; breadth, 1 1 ; depth 7 ; 

 W. carinata var. crewJcernensis — Length, 13; breadth, 10; depth 

 8 lines. 



Localities. — Bradford Abbas, Broadwindsor, etc. (Dorset) ; 

 Crewkerne Station, Stoford, etc. (Somerset) ; also near Stroud 

 (Grloucestershire), and Dinnington ; also near Bayeux, St. Vigor, 

 Salty, etc. (France), and Greisingen, G-ammelhausen, etc. (Swabia), 

 Balin and Luszowice. 



31a, — Waldheimia carinata, variety Blakei, Walker. 



1878. Waldheimia caeinata var. Blakei, Davidson, British 

 Brach. Palseont. Soc, supplement plate 

 xxiii., figs. 19, 20. 



Mr. J. F. "Walker informs me that he quite agrees with this 

 determination. Our specimens come from the opalinum zone at 

 Stoke Knap and near Haselbury, so that the horizon would 

 seem to be the same there as in Yorkshire, where they are quoted 

 from blocks of Shelly Dogger, belonging to the Yellow Sands, 

 Cliffs, near Scarborough. Our specimens, however, vary some- 

 what in shape and in the depth of the sinus, belonging to the 

 smaller valve. The beak is somewhat incurved. They differ 

 from Wald. carinata in being much shorter in proportion. 



Dimensions, ordinary size. — Length, 7 ; breadth, 7 ; depth, 3 

 lines. 

 Another Specimen. — Length, 9 ; breadth, 9 ; depth, 6 lines. 



Localities. — Stoke Knap (Dorset), near Haselbury (Somerset), 

 also near Scarborough (Yorkshire). 



