36 | Notices of Memoirs—Limestone Knolls of Craven. 
a necessary warning in the case of the Bokkeveld Beds with their 
diverse lithological development, and in view of the absence of 
minute zonal work or zonal collecting from the beds included in this 
stratigraphical series. 
' 4, In the case of the Mollusca Professor Schwarz is able to record 
several new species. Perhaps with regard to the specimen identified 
as Cypricardella Pohli, Clarke, the figure leaves something to be- 
desired, as, comparing it with.the one given by Clarke of this species,’ 
there ‘does not seem to be much resemblance. However, without: 
seeing the specimen a fair criticism cannot be passed. 
' 5. With regard to the trilobites and the points of difference: 
between Professor Schwarz and Mr. Lake in their identification, it is. 
not for me to pass any opinion. A small collection recently presented. 
by the South African Museum to Cambridge includes a good example. 
of the new species Homalonotus hippocampus, Schwarz, which, as the: 
author states, is sharply separable from H. Herscheli. 1 notice the 
subgeneric name Crypheus still used by Prof. Schwarz in connection’ 
with Phacops, though it has been shown to be preoccupied (GuOL. 
Mae., Dec. V, Vol. II, 1905, p. 173), and it is doubtful if any 
of the South African forms referred to this subgeneric group, 
Asteropyge, can be rightly retained in it without undue extension 
of its meaning. 
In a subsequent article a review of the whole fauna will be given. 
NOTICES OF MEMOTRS. 
SS 
I.—A Conrrisurion To our KNOWLEDGE oF THE LimEsToNE Kworis 
oF Craven. By A. Wiimors, F.G.S.' 
fJ\HE Craven Lowlands district, between the great faults on the 
| north-east and the grit hills of the Pendle Range on the south, is 
characterised by a well-known series of limestone knolls which have. 
been the subject of much discussion.” Having worked in the district 
for some years I venture to make the following suggestions. 
I. The words ‘knoll’ and ‘reef-knoll’ seem to be differently 
understood by different workers. It seems to me desirable to drop the 
term ‘reef-knoll.’ This term was applied by Mr. Tiddeman to certain 
extreme members of a series: there is every possible gradation between 
these and ordinary rounded knolls to which the term would never be 
applied. Further, the hills so named by Mr. Tiddeman have not all 
originated in the same way. 
1 Paper read in Section C (Geology) at British Association Meeting, York, 1906. 
2 Tiddeman: Brit. Assoc. Rep., 1899; Brit. Assoc. Handbook for Leeds and 
Airedale, 1890; Brit. Assoc. Rep., 1900; Grou. Mac., January, 1901. Marr: 
Q.J.G.S., vol. lv, pt. 3 (August, 1899) ; also Dakyns in same number. W. Hind & 
Howe, ‘“‘ On the Pendleside Group at Pendle Hill, etc.’’: Q.J.G.S., vol. lvii, pt. 3 
(August, 1901). Sir A. Geikie: ‘‘ Text Book,”’ vol. ii (1903), p. 1041. 
