ON THE CRETACEOUS FOSSILS IN ABERDEENSHIRE. 339 



Cretaceous forms, the Vectian element in the fauna is clearly very strong 

 — so strong indeed that I am led to doubt the existence of some of the Upper 

 Cretaceous species which have been supposed to occur. I therefore offer 

 some remarks on certain species, and give a complete revised list of the 

 Moreseat fauna, so far as it is at present known. 



Micrabacia coronida, Goldf. — This identification requires confirmation. 

 It depends solely on Salter's authority, for tlie specimen he saw is not in 

 the Jermyn Street Museum, and no other specimen has been detected in 

 the collections recently made. The species is not known to occur below 

 the Upper Greensand (zone of Pecten asper), and would be difficult to recog- 

 nise from a cast only. 



Echinoconus castanea, Brong. — This also requires confirmation, for the 

 specimen so named by Mr. Salter has not been found at Jermyn Street, 

 and no other example has been seen. In England its earliest appearance 

 is near the top of the Upper Greensand, but in Switzerland it ranges down 

 to the base of the Gault (see de Loriol in Echinologie Helvetique), so 

 that it may in some localities range even lower. No species of Echino- 

 conus, however, has yet been recorded from rocks of Lower Cretaceous 

 age. 



Discoidea decorata{1), Desor. — This specimen was among those sent by 

 Mr. Milne. It consists of a nearly perfect external mould in two parts. 

 It differs from D. subucidus in having close-set rows of nearly even-sized 

 tubercles ; eight rows on the interambulacral areas, four on each set of 

 plates ; and four rows on the ambulacral areas, but the two inner rows do 

 not reach either to the apex or to the peristome. The mouth and vent 

 are both rather large. In these respects it agrees with D. decorata. 



Mr. C. J. A. Meyer having informed me that he possessed specimens 

 of a Discoidea from the Vectian of Hythe, the Moreseat specimen was 

 sent to him for comparison. He reports that it agrees with those from 

 Hythe, but he is doubtful whether they are referable to J), decorata, Desor, 

 or D. macropyga, Ag. Both are Lower Cretaceous species. 



Bhyncho7iella comjyressa. — The specimen so named by Salter is at 

 Jermyn Street, and has been examined again by Messrs. Sharman and 

 Newton, with the result that they think it is only a compressed variety of 

 Rh. sulcata. 



Waldheimia faha, d'Orb. (non Sow.). — This being only a cast and the 

 shell being smooth, one cannot be quite sure of the species, but the shape 

 is well preserved, and I am indebted to Mr. Meyer for pointing out that 

 it has the squareness toward the front which is characteristic of the species 

 in question. This is well shown in the example figured by Davidson 

 ('Cret. Brach.' Vol. iv., PI. vi., f. 12-14), which came from the Speeton 

 Clay of Knapton in Yorkshire. 



Lima semisulcata, Sow. — This species has appeared in previous lists 

 on the authority of Mr. Salter, but the specimen is in the Jermyn Street 

 Museum, and Mr. Newton informs me that it is only an internal cast, and 

 may, with equal probability, be referred to L. Dupiniana. As specimens 

 of the latter do occur, and none referable to L. semisulcata have since been 

 found, I think this Upper Cretaceous species may be omitted from 

 the list. 



Area securis, d'Orb. — I have ventured to enter the common Area of 

 the Moreseat sandstone under the name of securis instead of under cari- 

 nata, because the specimens I have examined seem to me to come neai-er 



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