Cephalopoda in Tate and Blake's ‘ Yorkshire Lias.' 287 
Harpoceras simile Simpson sp. (p. 304). 
The original of PI. I., fig. 4, is in the Blake collection [B.M. No. C. 
1 79°5]- It is figured of about the natural size, but reversed. Various 
features of the fossil have been so clearly copied that there can be no 
doubt whatever about this being the figured example. It was not 
labelled when received with the -Blake collection. The • Geological 
position ’ of the species given by Blake is ‘ Zone of A . serpentinus , 
Whitby, etc v (Simpson),’ and it is, therefore, to be concluded that the 
figured example is from the Zone and locality mentioned. 
Harpocevas lythense G. Young and J. Bird sp. (p. 304). 
A specimen in the Blake collection [B.M. No. C. 17906] is evidently 
the' original of his PI. II., fig. 4. The figure depicts the fossil of about 
one -half the natural size and is not reversed. The greatest diameter of 
the specimen is 198-5 mm. When, received with the collection it was 
labelled in Blake’s handwriting, ‘Ammonites lythensis, Upper Lias, 
Whitby,’ on the side opposite the figured side, and on the figured side 
merely the figure ‘4.’ The latter most probably indicated the number 
of the figure on Plate II. The ‘ Geological position ’ of the species given 
by Blake is ‘ Zone of A. communis, Whitby, Passim.’ 
Harpoceras exaratum G. Young and J. Bird sp. (p. 305). 
The Blake collection includes a specimen [B.M. No. C. 17907], which 
is represented of the natural size in Blake’s PI. II., fig. 5, the details of 
the piece of matrix at the anterior end being clearly indicated. When 
received, the specimen bore no labels and no indication whatever of its 
being a figured specimen. Since the ‘ Geological position ’ given by Blake 
for this species is : ‘ Zone of A. serpentinus, Whitby, etc.,’ it may 
safely be considered that the figured example is from Whitby, and 
from the zone mentioned. 
Harpoceras primordiale Scholtheim sp. (p. 306). 
A specimen in the Blake collection [B.M. No. C. 17908] can, by the 
form of the fractured surface near the aperture and other details, be at 
once definitely recognised as the original of his, PI. II., fig. 7. Although 
not so indicated on the plate, the figure is much reduced, the largest 
diameter of the fossil being 224 mm. The specimen bears neither labels 
nor writing of any kind, unless some hieroglyphics on the fractured 
anterior end have any significance. Even these have somewhat the 
appearance of a private price-mark. There is, however, no doubt 
whatever about the identification of the specimen as the original of the 
figure. The ‘ Geological position ’ of the species as given by Blake is : 
‘ Zone of A. communis (towards the base), Whitby,’ so that this must 
be regarded as the horizon and locality of the figured example. 
Harpoceras latescens Simpson sp. (p. 308). 
A completely-septate specimen in the Blake collection [B.M. No. 
C. 17943] labelled in Blake’s handwriting: ‘A. latescens, U. Lias, 
Pl. C., fig. 7 ,’ is obviously the fossil represented of about the natural 
size on PI. VIII., figs. 7 a, 7 B. The label bears no locality, but since 
the ‘Geological position’ given by Blake is only : ‘ Zone of A. ser- 
pentinus, Whitby,’ this must be regarded as the horizon and locality of 
the figured example. 
Harpoceras compactile Simpson sp. (p. 308)'. 
The original of Blake’s PI. VIII., fig. 6, is evidently a specimen in 
his collection [B.M. No. C. 17944] exposed on the surface of a small 
lump of matrix, the figure representing the fossil of about the natural 
size. Further, the fossil is labelled in Blake’s handwriting : ‘ Ammon- 
ites compactilis, Peak cliff, Fig. 6, Y.L P [i.e., Yorkshire Lias]. The 
‘Geological position ’ of the species as given by Blake {op. cit., p. 308), 
is : ‘ Zone of A. jurensis, Peak.’ 
1922 Aug.-Sept. 
