426 — L. Richardson—Ammonites from the 
a case of “‘ heterogenetic homceomorphy ”, perhaps induced by 
similarity of habitat. On the evidence at present known, I am 
inclined to consider it as representing either the common stock 
from which both Pyrina and Conulus arose (though not by any 
means the actual radicle itself), or else as an offshoot from the 
Pyrina stock parallel to the Conulus line, but overreaching the 
Conulus stage. 
EXPLANATION OF PLATE VII. 
Fig. 1.—Conulopyrina anomala. Adapical view. Natural size. All ornament 
omitted in this and three following figures. 
Fig. 2.—Conulopyrina, anomala. Adoral view. Natural size. The actual 
peristome margin is obscure in the original ; see text. 
Fig. 3.—Conulopyrina anomala. Posterior view. Natural size. 
Fig. 4.—Conulopyrina anomala. Side view. Natura] size. The broken line 
near the bottom of the figure represents the peristomal concavity of the 
adoral surface. 
Fig. 5.—Conulopyrina anomala. Apical system enlarged. 
Fig. 6.—Conulopyrina anomala. Detail of parts of the adapical surface midway 
between apex and ambitus, taken in a place where the sutures of the 
ambulacrals are visible. 
Fig. .7.—Conulopyrina anomala. Area III and contiguous interambulacral 
columns. Only primary tuberclesshown. Ambulacral plating not inserted, 
but occasionally determinable as “‘ Pyrinid”’ on both adoral and adapical 
surfaces. The broken. curve across the figure is the line of the ambitus. 
Ammonites from the Upper Lias, Railway-cutting, 
Bloxham, Oxon. 
By L. RichHarpson 
MMEDIATELY east of Bloxham Station is a cutting through the 
Marlstone and basement beds of the Upper Lias. The Liassic 
deposits are now for the most part hidden by vegetation, but when 
the line was made and for some years subseyuently large numbers of 
fossils—principally ammonites—were collected from them. Several 
geologists have published particulars concerning the section! The 
writer has in his collection a number of ammonites from here, which 
have been examined by Dr. A. HE. Trueman. The object of this 
communication is to place on record the result of his examination. 
First, however, some particulars—mainly derived from accounts 
published by previous authors—may be given. The cutting is 
through the Marlstone and basement beds of the Upper Lias. At 
one place the beds are faulted, and about 3 feet of the “Sandy Beds” 
of the Middle Iias were exposed beneath the Marlstone. The Marl- 
stone is about 24 feet thick. No traces have been observed here of 
1 T. Beesley, Proc. Geol. Assoc., vol. v (1877), p. 168 ; T. Wright, ““ Monograph 
of the Lias Ammonites of the British Islands,” Palwont. Soc., pt. iii (1880), 
p. 128; E. A. Walford, Quart. Journ. Geol. Soc., vol. xxxix (1883), p. 229; 
Proc. Geol. Assoc., vol. xiv (1895), p. 177, ‘‘ The Lias Ironstone of North 
Oxfordshire,”’ Banbury and London (1899), p. 14; H. B. Woodward, “ The 
Jurassic Rocks of Britain, vol. iii—The Lias of England and Wales (Yorkshire 
excepted),’’ Mem. Geol. Surv. (1893), p. 269. 
