﻿78 MR. S. S. BUCKMAN ON CERTAIN [F eD - I9IO, 



IV. Remarks on Hemeral Terms. 



SdilcenbacJii. — This term was suggested by me in some MS. notes 

 to a paper by Munier-Chalmas x whence it was inadvertently copied 

 by Mr. Richardson. 2 It is a term for dating the strata which had 

 been hitherto called mter-truellii-zigzag. 3 



Whereas at the top of the ' Top Beds ' of Burton Bradstock there 

 is a distinct Ammonite fauna, Zigzagieeras spp., MorpJioeeras spp., 

 and ParJcinsonice of the clepressa type with rounded whorls, and of the 

 P. lewis (Quenstedt) pattern with involute trigonal whorls ; and in 

 the lower part of the ' Top Beds ' there is a fauna with Strigoceras 

 truellii, and ParJcinsonice of the P.-parJcinsoni type with flattened 

 whorls : there is in the 2nd Bed of Burton Bradstock and in the 

 lower part of the 1st Bed a series of ParJcinsonice different in 

 character from those above or below — they are massive forms with 

 stout, somewhat squared whorls. 



Thus, on the evidence of Burton and other Dorset localities, there 

 is need to recognize a date of deposition later than truellii and 

 earlier than zigzag hemera. But Mr. Richardson's investigations 

 in Somerset have shown that this refinement was most necessary ; 

 for between strata of zigzag date (there basal Fullers' Earth) and 

 strata of truellii date (Upper Coral Bed) he finds three noticeable 

 deposits — Rubbly Beds, Anabacia Limestones, and Doulting Stone 

 (loc. cit.) ; and, as regards the Cotteswolds, he would put the Glypeus 

 Grit (sometimes over 30 feet thick) as belonging to this date. 4 



SJiirbuirnice. — The deposit of this date was formerly known as 

 hemera Sonninice, but a generic rearrangement of the numerous 

 forms of Sonninia will have to be undertaken. The true Sonninice, 

 the platyleptogyral, angustumbilicate, alticarinate species of the 

 Sonninia-propinquans type, are found only in a deposit of sauzei 

 date. 



The type-species of the genus SJiirbuimia will be described in 

 the palaeontological paper (pp. 92 et seqq.). 



The deposit of SJiirbuirnice hemera is noticeable, because it is of 

 the date of the celebrated deposits of Gingen (Wurtemberg), the 

 Ammonites from which were described by Dr. W. Waagen. 



In this country a deposit of SJiirbuirnice date is only found in per- 

 fection at one quarry, Sandford Lane near Sherborne (Dorset), where 

 it forms the bottom part of the fossil-bed. Here it has produced an 

 extraordinary abundance of remarkable Ammonites, most of which 

 are new : they have waited over 40 years to be figured and described. 

 And in this country the channels for palaeontological publication 

 are becoming more and more unable to keep pace with the new 

 discoveries of geologists. 



1 C. R. Soc. Geol. France, 1892, no. 14, pp. 164-67. 



2 Proc. Cotteswold Nat. F.-C. vol. xvi, pt. 2 (1908) p. 188. 



3 L. Richardson, Quart. Journ. Geol. Soc. vol. lxiii (1907) p. 423. 



4 Proc. Cotteswold Nat. F.-C. vol. xvi, pt. 2 (1908) p. 187. 



