338 Recent Discoveries in the Chalk of the Flamhoro' District. 



are quite sufficieni: to enable it to be determined generically. 

 The chief interest in this specimen lies in the fact that it 

 compares well with the contemporaneous forms in the German 

 Cretaceous strata. Cephalites hullatus — a particularly fine 

 specimen of Hexactinellid sponge was collected recently in the 

 Marsupites zone, west of Danes' Dyke. Although the com- 

 moner varieties of sponges [Seliscothon, etc.) are plentiful at 

 about this horizon, the above species probably has never been 

 recorded before from the Yorkshire Chalk. 



Perhaps the most interesting specimen collected among the 

 sponges is a portion of a large Ventriculites which must have 

 attained gigantic proportions. Local geologists are fairly 

 familiar with the Ventriculites of the Upper Chalk, but, as a 

 general rule, they seldom exceed a length of 12 inches. As 

 in all this class of sponge the radial canals intersect in a charact- 

 eristic reticulate manner, the meshes of which measuie \ inch 

 in an average specimen. In the recently found Ventriculites, 

 however, the reticulations have an average length of f inch. 

 Thus it has been estimated by Mr. Sherborn that this specimen 

 must have been at least 6 feet in total length. As far as he 

 is aware this is the largest Ventriculite which has ever been 

 collected from the English Chalk. Among the cephalopods 

 of the inland quarries of the Flamborough district (Bessingby 

 and White Hill) the most interesting forms are the Scaphites. 

 In a typical specimen the shell is coiled in a plane spiral. 

 The whorls are in contact, except the last, which is free from 

 the spiral and then recurved in the form of a hook. The sur- 

 face of the shell is ornamented with bifurcated ribs and often 

 bears tubercles. Two varieties are common to the Yorkshire 

 Chalk, Scaphites binodosus and S. inflattis. As a general rule 

 the scaphites have a tendency to occur in definite layers or 

 zones and consequently prove valuable indices to the various 

 horizons. 



Other specimens recently added to the Hull Museum 

 collections are : — 



Ostrea vesicularis. 

 Holaster sub-globosus. 

 Parasmilia centralis. 

 Cidaris (young). 

 Micr aster (young). 

 Infulaster rostratus. 

 Plicatula spinosa. 

 Pleurotomaria sp. 



Camerospongia. 

 Inoceramus lobatus. 

 Inoceramus lamarcki. 

 Micr aster cor-anguimim. 

 Avicula tenui-costata. 

 Spondylus latus. 

 Seliscothon planus. 



My thanks are especially due to Mr. C. Davies Sherborn, 

 who has kindly named the majority of the specimens. 



In the natural history section of the British Museum, a special exhibit 

 has been arranged to illustrate the British Lower Carboniferous rocks 

 and their fossils. 



Naturalist, 



