TT. jET. HucUeston — On the YorTcshire Oolites. 151 



III. — Contributions to the Paleontology of the Yoekshieb 



Oolites. 

 By Wilfrid H. Hudleston, M.A., F.R.S., F.G.S. 



(Continued from Decade III. Vol. II. p. 129.) 



(PLATE IV.) 



80. — Pleukotomaria depkessa, Phillips, 1829. Plate IV. 



Figs. 1, 2, 2a. 



1829, 1835. Cirrus depressus, Phillips, G. Y. p. 112, plate vi. fig. 12. K.R. 

 1849. Pleurotomaria depressa, D'Orb. Prod. i. p. 333. Et. Cal. 

 1854. depressa, Phil. Morr. Cat. p. 271. 



1859. Pleurotomaria striata, Bean, MS. Leckenby, Q.J.G.S. p. 12, pi iii. fig. 2. 



1860. Pleurotomaria Montreuilensis, H. and D. Foss. Mont. Bellay, p. 68, pi. t. 



fig. 3. 

 1860. Pleurotomaria striata, Leek. Op. cit. pi. t. fig. 4. 



1875 ( ^^^'-"'o^o'^"^''"- '^''P^'^^^Cj Pbil.) As distinct species, Phillips, G. Y. 3rd ed. 

 \ Pleurotomaria striata, Leek, j" p. 250. 



Bibliography, etc. — Phillips's type was evidently a cast from the 

 Kelloway Eock, of Hackness, near Scarborough. I have not been 

 able to identify the original, which was supplied by Bean. The 

 figure, however, plainly shows it to have been a cast of a good-sized 

 discoidal shell, and there are specimens now in the Bean Collection 

 at the British Museum not unlike it. 



On the other hand, Bean's Cirrus striatus, described and figured by 

 Mr. Leckenby (Fig. 2 of our Plate), having been preserved in the 

 hard grit of the Kelloway Eock, exhibits what was probably a 

 faithful outline of the original shell. At first sight there would, 

 seem to exist no connexion whatever between the two ; but when 

 we examine such a specimen as the one I have described but not 

 figured (see second description), the relationship between the cast 

 and the shell becomes more easy to understand. It is to be regretted 

 that the rule of priority should be allowed to extend to species 

 founded on casts, especially when there is not a word of description. 

 But Mr. Leckenby himself appears to have acquiesced in the adoption 

 of the rule, since we find the type of PI. striata is placed in a tray 

 with two other specimens in the more usual condition, the tray being 

 labelled PI. depressa, Phil. 



If we wish to see what a well-developed and well-pi'eserved shell 

 of Pi. depressa is like, we maj'^ turn to Hebert and Deslongchamps 

 figure of PL striata, Leek., and I think there can be little doubt 

 that PI. Ifontriieilensis of the same authors is so near that it may 

 well be placed in the same category. 



Descriptions. — Specimen from a hard grit of the Kelloway Eock 

 (zone 5), Castle Hill, Scarborough. Leckenby Collection. Type 

 of PI. striata refigured. Fig. 2. 



The following is Mr. Leckenby's description : — " Shell depressed : 

 whorls four, tabulated ; keel slightly prominent, transversely ridged, 

 and crossed by numerous very fine oblique irregularly undulating, 

 raised lines, which pass uninterruptedly over the keel." Our artist 



