W. S. Hudleston — On the Yorkshire Oolites. 147 



Varieties of the bispinosa-trijida group been found in any of these 

 three zones. On the other hand, the liamiis group is entirely absent 

 from the Cornbrash, and all the Oxfordian beds. This complete 

 separation of the two groups does not seem to occur elsewhere to 

 such a marked extent. 



Amongst the specific characters of Alaria the most important, 

 according to Piette, are — the form of the canal, its direction and 

 mode of increase ; the number of digitations, their form and direc- 

 tion ; the number of keels on the last whox"l, their relative size. 

 The prolongation of the spire is more or less great, the convexity of 

 the whorls is more or less strong, but never in the same species does 

 a hollow replace a convexity ; the number and arrangement of the 

 fine spiral lines is not of specific importance. Unfortunately, we 

 can but guess at some of the characters above indicated in dealing 

 with the specimens from the Yorkshire Oolites. 



36. — Alaria hajius, Deslongchamps, var. Phillipsii, D'Orbigny. 

 1842. Plate VI. Figs. 3, 3a, 4. 



1829 and 1835. Eostellaria composita, Sow. Phillips, G. T. pp. 124, 129, 165, 



pi. ix. fig. 28. 

 1842. Rostellaria hatnus, Deslongchamps. Mem. Soc. Linn. Norm. vol. vii. p. 173, 



pi. ix. figs. 32-36. 



1849. PferoC(?ra"P/?i/^>su, D'Orbigny, Prod. i. p. 270. 



1850. Alai-ia Phillipsii, D'Orb. ? Rost. hamus, var. /3 Desl., Morris and Lycett, 



Great Ool. Moll. p. Ill, pi. xv. figs. 15, 15«. 

 1875. Alaria Phillipsii, D'Orb. Phillips, G. Y. 3rd edition, p. 258, pi. ix. fig. 28., 



Bibliography, etc. — ;The original Eostellaria composita, Sowerby 

 (Min. Conch, t. 558, fig. 2), may truly be described a composite 

 species. " One specimen more sti-ongly costated than the others was 

 picked up at Weymouth in the Oxford Clay ; others have been sent 

 us from Scarborough, but the only ones that have the lip preserved 

 were collected at Brora in the stone immediately above the coal." 

 Although Sowerby did not happen to figure any of the Scarborough 

 specimens, there is no question that he was referring to such as are 

 found in the Scarborough Limestone and Millepore Rock, and hence 

 Phillips had some excuse for referring them to Sowerby's lately 

 constituted species.^ 



It should be noted that Phillips described the Yorkshire species 

 now under consideration as occurring both in the " impure limestone " 

 of Cloughton and Brandsby, and likewise in the Inferior Oolite Sand 



^ On examining the collection of Sowerby's types at the British Mnsenm, in com- 

 pany with Mr. Etheridge and Mr. Newton, we found that, besides the two figured 

 forms, there were several other specimens fixed to the card. One of these comes from 

 the Doggier of the Peak, and is almost identical with the form in the accompanying 

 Plate (VI. Fig. 5). Two others are from the Millepore Rock, or from the 

 ferruginous bed of the Scarborough Limestone, and are good examples of AL 

 haviKs, var. Phillipsii. Of the figured types themselves, the one from Weymouth 

 has been preserved in a hard concretionary ironstone strongly reddened, Avhich 

 probably came from the base of the Oxford Clay, here devoid of any specialized 

 Kellaways Eockl The other, from the roof of the Brora coal, is likewise on the 

 same horizon. Hence, Rosteltaria composita, Sow., is to be regarded as a Callovian 

 form, very similar to, if not identical with, Eostellaria seminuda, H. and D., from 

 the Callovian of Montreuil Bellay. 



