THE RED CHALK OF HUNSTANTON. 455 



from tlie Upper Chalk at Chatham. Thanks to the kindness shown 

 towards me by Prof. Judd, r.E.S.,and Dr. Pergens, of liolgium, I have 

 been enabled to study the Polyzoa of the Taxoe Limestone and 

 Maastricht Beds, by the gift of beautiful examples derived from 

 these typical horizons of Cretaceous Polyzoa. 



In the ' Catalogue of the Cretaceous Possils in the Museum of 

 Practical Geology,* 1878, we have lists of a fair assortment of 

 British examj^les from several horizons, but there are many unavoid- 

 able blanks. Out of nine Cretaceous divisions given in the Catalogue, 

 in four important sections there is no mention of a Polyzoan fauna. 

 In the Neocomian (Lower Greensand) division (pp. 0, 7) much of the 

 material is still un worked; but at least twenty-one forms are named 

 specifically. These belong to the following genera : Stom(ito2:)ora, 

 Bronn ; Proboscina, xludouin : Diastopora and Entalu_i)]ior(i^ 

 Lamouroux, together with species of Ceriopora^ Hetei'upora, and 

 Hadiopora. The locality from which most of these Polyzoa were 

 derived was Earingdon, but other localities are mentioned. In the 

 Gault (pp. 26 et sec/.) there is no record of Polyzoa ; but in the 

 Blackdown seiies (p. 39) there are four entries under the head-line 

 " Polyzoa." In the Upper Greensand (Cenomanian, pp. 49-50) 

 there are fifteen species named, besides refereiices to others, most of 

 which are from Warminster. In the Cambridge Greensand, 

 Chloritic Marl, and Ked Chalk there is likewise no mention of 

 Polyzoa. In the Lower Chalk (p. 83) two references are given ; and 

 in the Upper-Chalk division of the Catalogue (p. 95) twelve species 

 are named in full. 



It is hard to account for this poverty of a polyzoan fauna in many of 

 our own Cretaceous beds otherwise than by supposing that probably it 

 arises from other causes than mere absence, and one of the chief may 

 be that of British workers on the group being so few. In foreign 

 localities the Cretaceous beds have been well worked, the upper 

 divisions especially, and the number of species described by Goldfuss, 

 von Hagenow, d'Orbigny, von Eeuss, and others, though considerable, 

 are still being added to by persistent and careful research, whilst 

 our own strata are at present characterized as poor in Polyzoa. 



Independently of the species catalogued as existing in tlie !^[useum 

 of Practical (ieology, or referred to by Morris in his ' C-atalogue of 

 British Fossils,* lists of Polyzoa from certain Britisli Cretaceous 

 horizons below the Upper Chalk are extremely rare, and I am not 



aware tlmt any exist except those mentioned 



. below. 



Mr. Ethe- 



ridge, F.ll.S., gives * the following summary 



of known 



Cretaceous 



Polyzoa : — 







Upper Chalk. ... 38 genera, 5U 



species. 





liower Chalk . . (i „ 







Chalk-marl .... 1 genus, 1 







(■enomanian .... 15 genera, 24 







(iault 3 „ 4 







Neocomian .... 21 „ 34 







PhiUps, 'Manual of Geology and rala'ontologv,' vol. ii. 138;"), p. .')8l, 



2 K 2 



