420 Professor H. L. Hawkins— 
lat. 34° 40’ N.), might have been partially due to such a dramatic 
physiographical change that had upset the pre-existing drainage 
systems. The fact that ancient seaports on the coast of Pe-chi-li 
are now found many miles inland is also in favour of this argument. 
In the eastern part of the Great Red Basin of Su-chuan the Yang- 
tze flows towards north-north-east in spite of the increasing mean 
altitude of land towards that direction. Clearly then the middle 
part of the river, which cut into the late Tertiary or even Quaternary 
sandstones, must be antecedent to the recent upheaval of the Tsing- 
ling area. 
It is hoped that these working hypotheses drawn from very incom- 
plete data may serve to arouse the interest of field geologists, by 
whose accurate record of detailed observations alone the question of 
their acceptance or rejection may be finally settled. 
In spite of the great demand of space, the writer cannot let this 
opportunity pass without expressing his gratitude to Professor W.S. 
Boulton for his college training, especially during the preparation of 
a thesis of which the present paper is a precis; and his obligation 
to Dr. L. J. Wills, M.A., who cordially made several valuable 
suggestions and criticisms relating to the arrangement of material 
in this paper before it was put in the present form. 
Morphological Studies on the Echinoidea Holectypoida 
and their Allies. 
XI. CONULOPYRINA ANOMALA, A NEW TYPE OF THE 
ECHINONEIDZ.. 
By Herbert L. Hawkins, D.Sc., F.G.8., Professor of Geology, 
University College, Reading. 
(PLATE VII.) 
MONG the Echinoids from the Limestone Lenticles of Shenley 
Hill (Leighton Buzzard), sent to me from the Sedgwick Museum, 
Cambridge (see Grou. Maa., Vol. LVIII, 1921, p. 57), one specimen 
of the many Pyriniform examples at once attracted attention by its 
preservation, relatively large size, and superficial resemblance to 
Holectypus. A brief comment on the specimen (No. 3 of the series) 
was made in the note already cited; further and more detailed 
examination, preceded by removal of matrix, has revealed additional 
features of much interest. Though averse to diagnosis of new genera 
or species based on single specimens, I have felt compelled to adopt 
that course in this case, in default of acquaintance with any described 
types to which the Shenley Echinoid could be assimilated. It is 
quite likely that other specimens, congeneric if not conspecific, 
may exist in collections; according to their preservation or the 
idiosynerasy of individuals they may be labelled Holectypus, 
—Conulus, or Pyrina with equal probability. It is even possible that 
some of the numerous species of Pyrina (including Pseudopyrina 
