Tol. 52.] OF THE CHALK EOCK. 83 



it to S. cequalis of Sowerby. D'Orbigny recognized it as being 

 •distinct, and gave it the name Geinitzi, but it was first figured as 

 such by Romer (1870). Later figures and descriptions have been 

 given by Schliiter, Fritsch, and Geinitz. 



Ammonites Cottce of Eomer (1841) has been shown to be simply 

 -the involute part of Seaphites Geinitzi. The same, I believe, is the 

 •case with Sharpe's Ammonites wiltonensis ; the type of this species 

 was collected by Mr. W. Cunnington from the Chalk Rock of 

 ■Oldbury Hill, 7 J miles E.S.E. of Warminster, and is now in the 

 British Museum ; the form of the shell, as well as its ornamentation 

 :and suture-line, agrees perfectly with Seaphites Geinitzi. 



By some authors this species has been recorded from the Chalk 

 "Rock as S. cequalis — a form which, is not found in the Turonian. 



In the Survey Memoir on Cambridge, 1 Seaphites cequalis (?) is 

 recorded from the zone of Holaster planus of Ickleton : the specimen 

 ds now in the Jermyn Street Museum, and is, I believe, referable to 

 8. Geinitzi, but it is not sufficiently perfect to be determined with, 

 •certainty. Whitaker 2 records Seaphites sp. from the Upper Chalk 

 of Mario w, but the specimen has apparently been lost. 



Affinities. — Seaphites obliquus, Sowerby, from the Cenomanian, is 

 allied to the species under consideration, but differs from it in being 

 -thicker and in having the tubercles indistinct or faintly marked. 



S. cequalis, Sowerby, from tbe Cenomanian, is also a thicker form, 

 -especially in the bamus, the outer border of which is less rounded 

 than in S. Geinitzi, and the tubercles are costaeform. 



In S. infiatus, Homer, from the Senonian (zone of S. hinodosus) 

 of Westphalia, the row of tubercles is found on the involute as well as 

 on the evolute part, and extends to the aperture. The hamus is rela- 

 tively shorter than in S. Geinitzi, and the suture-line more divided. 



In S. hippocrepis (Dekay) = Cuvieri, Morton, from the argillo- 

 ferruginous sand of the Chesapeake and Delaware Canal, the row of 

 'tubercles is similar to that in S. Geinitzi, but extends to the 

 aperture. 



Distribution. — England : Chalk Bock of Dover, Winchester, Old- 

 borough Castle, Cuckhamsley, Prince's Bisborough, Boxmoor, Luton 

 cutting, Hitchin, and Underwood Hall near Dullingham. Perhaps 

 ^also in the zone of Holaster planus and in the Upper Chalk (? zone of 

 Mier. cor-testudinarium). France : zone of Epiaster brevis at Fontaine- 

 les-Vervins, zone of Micr. breviporus of Cambrai, zones of Hoi. 

 planus and Ep. brevis east of the Paris basin, zone of Spondylus 

 truncatus of the Loir-et-Cher, and ' Craie de Yilledieu/ North-iuestern 

 Germany : common in the zone of Heteroceras Reussianum throughout 

 "North-western Germany, rare in the zones of Inoe. Cuvieri and 

 Inoc. Brongniarti. Saxony : Planer-Kalk of Strehlen and Weinbohla, 

 and Seaphites-beda of Zatzschke. Silesia : Seaphites -beds of Oppeln. 

 Bohemia : through the Turonian and in the Priesen Beds ; found 

 at Priesen, Teplitz, Bohmisch-Kamnitz, Waldeck, etc. Bavaria : 

 Kagerhbh Beds of the Buchleitner Bruch, near Passau. 



1 Penning and Jukes-Browne, ' Geol. Neighbourhood of Cambridge ' (1881), 

 jp. 65. 



2 'Geol. London, etc/ vol. i. (1889) p. 81. 



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