176 mr. c. Thompson on the [June 1913, 



Annulatum Beds. 



The passage-beds to the Upper Lias or the Annulatum Zone 

 have yielded to the ice, so far as is known at present, all the 

 Yorkshire forms, except the rare Lytoceras cornucopia. 



Spherical or ovoid nodules, yielding many good examples of Dacty- 

 lioceras annulatum or of Pseudolioceras elegans, are fairly frequent. 

 Every collector of Yorkshire-Drift fossils soon finds a good example 

 of the former. 



Serpentinum Beds. 



When one examines the fossils derived from the old Serpentinum 

 Zone, one sees many beautiful examples of its grand fauna. The 

 genus Hilcloceras is well represented by H. bifrons Brug., also by 

 kindred forms which pass locally under the same name. I have 

 not yet been able to secure a true H. serpentinum Rein, from York- 

 shire, but I have found a very near relative in H. boreale Seebach. 

 The falciferi are also frequently present, and the Drift has yielded 

 two of them new to English lists. The appended list (p. 181) 

 shows an expansion of the genus Pseudolioceras, which seems to 

 need a great amount of attention before it becomes thoroughly 

 known. Mr. Truckman informs me that he has found similar 

 examples in the Museum of Practical Geology, Jermyn Street. 



Commune Beds. 



The zone of Dactylioceras commune has also contributed much 

 material to the Drift. Of course, the name-fossil of the zone is 

 found everywhere. I have been able to add very little to the list 

 of recorded species from the zone, although the three predominant 

 genera — Dactylioceras, Coeloceras, and Peronoceras — yield many 

 species to the collector. 



Jurense Beds. 



From the Jurense Beds we have found a few representative 

 species, which do not look so feeble when one considers how small 

 is the Yorkshire list for that zone. It is known, however, that 

 when the zone in situ can be properly worked there will be a far 

 larger number to search for in the Drift also. 



Liassic Nautili and Belemnites. 



The nautili of the Lias are present in the Drift, though rarely, 

 and then are in such a condition that difficulty is experienced in 

 naming them ; therefore two only are included in the appended 

 list. 



Belemnites are abundant: but, owing to their crystalline structure, 

 those of the Lias are broken up usually into very small pieces ; 

 hence the list given here is small. 



