C. Davies Sherhorn — Irregular Chalk Echinoids. 31 



VI. — Eemarks on the Irregular Echinoids of the White 

 Chalk of England as exhibited in the British Museum 

 (Natural History). 



By C. Davies Sherborn, F.G.S. 



HAVING been asked by Dr. Smith Woodward and Dr. Bather 

 to look over the collection of Irregular Echinoids from the 

 English Chalk in the British Museum virith a view to bringing the 

 exhibition up to date, it appears a favourable opportunity to say 

 a few words as to the nomenclature and distribution of these animals. 



Until Dr. A. W. Kowe has completed his study and given us the 

 result of his examination of his own splendid collections, it is im- 

 possible to give more than a brief outline of the subject, for he, and 

 he alone, has the material necessary for a detailed report. The bulk 

 of the material in our National Collection has been acquired by 

 donation or purchase, and that at a time when zones or localities were 

 considered of little importance, whereas Dr. Eowe's material has all 

 been collected by two persons, with the definite object of showing 

 the evolution of the animals and the resulting progressive change 

 into forms of more or less value. While, therefore, the National 

 Collection is invaluable from a zoological point of view, it is 

 practically valueless for Evolutional Palseozoology. The present 

 exhibit has been obtained by the help of others, and the authorities 

 have to thank Messrs. Bather, Chatwin, Dibley, Rowe, Sherborn, 

 and Withers for specimens which show more or Jess completely the 

 history of each species as it is followed successively upward in the 

 zones of the White Chalk of this country. It has not been possible 

 to acquire specimens from each zonal occurrence of the rarer species. 



I will take the forms seriatim, making such notes as seem 

 necessary as I proceed : — 



Echinocorys scutatus, Leske : Addit, ad Klein, Nat. Dispos. Echin., 

 1778, p. 175, pi. XV, figs, a, b. This is the earliest name for 

 this urchin. Leske does not say where the type came from, 

 but it is a cor-anguinim form. The synonyms of this species 

 are M ovatus, Leske, Addit. ad Klein, etc., p. 178 ; E. vulgaris, 

 Orbigny (ex Breyn), Pal. Frany. (Cret. Ech.), 1854, p. 62, 

 pis. 805, 806. Eange : H. planus zone to Danian. 



Conulus albogalerus, Leske : Addit. ad Klein, Nat. Dispos. Echin., 

 1778, p. 162, pi. xiii, figs, a, b. This is the earliest name for 

 this urchin. Leske does not say where his type came from, 

 but it is a somewhat low (depressed) form from the cor- 

 anguinum zone. The synonyms are Galerites albogalerus 

 (Leske), Lamarck, Anim. sans Vert., iii, 1816, p. 20, and 

 Echinoconus conicus, Orbigny (ex Breyn), Pal. Fran9. (Cret. 

 Ech.), 1860, p. 513, pi. 996. Range: M. cor-testudinarium to 

 A. quadratiis zones. 



Conulus orbigny anus (Ag.). Galerites orbignyana, Agassiz, Mon. 

 Ech. {Galerites), 1842, p. 22, pi. iii, figs. 5-8. This is the little 

 bun-shaped Conulus found at Trimingham and in (?) the upper 



