part 1] of the shales-with-'beee.' 79 



which an example in the Natural History Museum (C 16416) 

 from Welford Hill (Gloucestershire) belongs. The true Schlot- 

 heimia attains its maximum development in lower bucklandi 

 times, with S. greenoughi (Sowerby) and allied gigantic forms. 

 The much later Sulciferites, representing Mr. Buckman's ' second 

 wave of Schlotheimia,'' developing such highly specialized types 

 as S. boucaultianus (A. d'Orbigny) and therefore not a ' cata- 

 morph,' represents an independent development, probably of 

 the same stock. It is possible that ' Angulaticeras ' of the 

 oxynotus zone, Mr. Buckman's ' third wave of Schlotheimia ' is 

 referable to yet another branch, although its connexion with 

 the family Schlotheimidse is uncertain. ' Schlotheimia'' sulcata 

 (Simpson non J. Buckman) belongs to this last group ; but 

 & clumortieri Fucini ( = S. deleta Canavari?), included here by 

 Mr. S. S. Buckman, is considered to be a Sulciferites of an 

 earlier horizon. 



Sulciferites probably represents a development of Schlotheimia 

 ventricosa (Sowerby) and S. posttaurina (Wanner), which are of 

 rotiforme age. 1 In areas where the intervening scipionianus and 

 ■sauzeanus zones are developed, as, for instance, in Skye, Yorkshire, 

 Saltrio, or Alsorakos, no Schlotheimia are found that might form 

 & satisfactory connecting-link, although in Warwickshire, as 

 already stated, Schlotheimia of the charmassei group are associated 

 with JEpammonites of the bucklandi beds. Hyatt considered 

 ' Ammonites charmassei Hauer ' and ' JEgoceras ' tenuicostatum 

 Herbich (the latter united with Schlotheimia marmorea by 

 Vadasz), to connect the Schlotheimids of the lower bucklandi 

 zone with the later S. angustisulcata and ' S. lacunata ' of Greyer; 

 and Wright assumed S. boucaultianus, known only in one British 

 (Lincolnshire) example, to be a direct descendant of Schlotheimia 

 charmassei of the lower bucklandi zone. In reality, there is a 

 very considerable gap between the Schlotheimia of the bucklandi 

 zone, especially the extra-Mediterranean forms, as, for example, 

 S. angulatoides (Quenstedt) from Wurtemberg, the horizon of 

 which is known, and the genus Sulciferites of the lower obtusum 

 zone. 'Schlotheimia'' d'orbignyana Hyatt in Schmidt, 3 from the 

 Harzburg Ironstone, somewhat bridges this gap, though its exact 

 horizon is unknown ; and derived fragments of S. angulata still 

 occur in bed I of the Harzburg Ironstone with Agassiceras 

 sauzeanum ; S. charmassei also has an intermediate position. All 

 the forms figured by Fucini from the Lower Lias of the Monte di 

 Cetona may be Sulciferites. On the other hand, Schlotheimia 

 angustisulcata Geyer, 3 a Hierlatz form, is not included in Sulci- 

 ferites, its suture-line being of quite a different type and not 

 simple like that of the genotype of Sulciferites. Now, Geyer 



1 F. Wahner, Beitr. Pal. (Est. Ung. vol. iv (1886) p. 200. 

 - Palfeontographica, vol. lxi (1914) p. 37 & pL vii, figs. 2-5. 

 8 ' Ueber die Liasischen Cephalopoden des Hierlatz bei Hallstatt ' Abhandl. 

 K. K. Geol. Eeichsanst. vol. xii (1886) p. 258 & pi. iii, figs. 24-25. 



