4 PROCEEDINGS OP THE GEOLOGICAL SOCIETT. [Feb. 1 894, 



3. ' On a Variety of Ammonites (Stephanoceras) subarmatus, 

 Young, from the Upper Lias of Whitby.' By Horace W. Monckton, 

 Esq., F.L.S., F.G.S. 



[Abstract.] 



The Author exhibited an ammonite found by himself in 1874 

 near Sandsend, 3 miles north-west of Whitby. He thinks it was 

 not actually in situ, but lying with a number of nodules on the 

 floor of an old alum-pit, although he has no doubt that it is from 

 the Alum Shale of the Upper Lias. A peculiar arrangement of the 

 costse as they cross the siphonal area distinguishes the specimen 

 from other Whitby ammonites known to the Author. It bears a 

 strong resemblance to a shell figured as A. subarmatus by D'Orbigny, 

 ' Terr. Jurass.,' pi. lxxvii., but is unlike the figures of that species 

 given by other authors. 



Discussion. 



Prof. J. F. Blake said that the ammonite in question seemed 

 nothing unusual. It would be included in the varieties or mutations 

 of subarmatus, the genus of which was not Stejphanoceras. 



Mr. George C. Crick also spoke. 



The Author, in reply, pointed out that he only claimed his fossil 

 to be a variety, not a new species ; and if a variety, it must be a 

 variety of some species. He thought it was less unlike A. sub- 

 armatus than other Liassic species. In any case, it was, he thought, 

 the A. subarmatus of D'Orbigny, and in assigning that species to 

 StejJianoceras he had simply followed Dr. Wright. 



In addition to the specimen described on the preceding page, the 

 following were exhibited : — 



Rock-specimens from Barnton, near Edinburgh ; and specimen 

 of Ammonites subarmatus, var., from the Lias of Whitby, exhibited 

 by Horace W. Monckton, Esq., F.L.S., F.G.S. , in illustration of his 

 papers. 



Specimens of Scottish Granite, exhibited by Horace W. Monckton. 

 Esq., F.L.S., F.G.S. 



December 20th, 1893. 



W. H. Hudleston, Esq., M.A., F.R.S., President, in the Chair. 



Arthur Hassam, Esq., Waverley House, Fenton, Stoke-on-Trent; 

 Robert Ludwig Mond, Esq., M.A., F.R.S.E., F.C.S., The Poplars, 

 20 Avenue Road, Regent's Park, N.W. ; and Llewellyn Treacher, 

 Esq., Somercroft, Twyford, Berkshire, were elected Fellows ; Dr. E. 

 Mojsisovics von Mojsvar, Vienna, and Dr. A. G. Nathorst, Stock- 

 holm, Foreign Members ; and Dr. S. L. Tornquist, Lund, a Foreign 

 Correspondent of the Society. 



The List of Donations to the Library was read. 



The following communications were read : — 



