FROM NORTHWESTERN EUROPE II 
are not in the area where they lived and this is borne out by the fact that onto- 
genetic series of T. obtrita can be collected. 
Concerning the remaining genus and subgenus, namely Monticlarella and Echi- 
nirhynchia, the latter is known to occur in all the facies previously described apart 
from in association with corals while Monticlarella is recorded from all except the 
near shore, high energy type. These observations, coupled with the small size of the 
Distribution of Oxfordian 
rhynchonellid genera 
Fic. 3. Ac=Acanthorhynchia ; La=Lacunosella; Rh=Rhynchonella ; “ Rh’’=‘ Rhyn- 
chonella”’ ; Se=Septaliphoria ; So=Somalivhynchia ; Th=Thurmannella. 
