- mmm;v H3 



ban 1" ipler with advancing age, and more like tho» ind by 



. of the latter, which, though found by Wahner, 1 ia declared to be rare. 



One <>!' Wahner'a specimens was transitional to // n its sutures, and this 



that the province of 1 1 1 « » Northeastern Alps was the autochthonous 



home '/«#«, jthwrh, . and // ind adds greatlj to the probabilities 



in favor of Neumayr's hypothesis. In Cal I nd nodotiamm it 



imon to find varieties varying in the Buturea between the Mediterranean 



and Centra] European extremes of modification, the latter bein se the 



ni"-t num< rous in their own province and rare in the Northeastern A 1 u~. The 



BUturet ind nodotiamu* when contrasted with Quenstedt's, 



ind our own figures, lod idea of the extent of variation, which 



is quit - i / ' r, if not greater. 



Undoubtedly these facts, and the nearer approximation in aspect and Buturea 

 of the M rranean forma of Psiloceraa to Gymnitea of the Trias, the genus we 

 have always regarded as the probable ancestor of the former, are Btrongly in 

 opinion thai the tonus <>i' the European province arose by 

 chorological migration from the apparently more ancient lamia of the Mediter- 

 ranean province. The richer evolution of triassic forms in the Mediterranean 

 province, as described and illustrated by Mojsisovics, can also be brought forward 

 in favor of thi> \ Kevertl eh ss, ii is n«>t right to yield entirely t<> tli" fasci- 



thia opinion until there ia positive proof that PaLpianorbt or caKphyllum 

 rred earlier>in tlii* province than in Central Europe. 



With regard to the origin of Caloceras from tliix province, the facts are still 

 . • >r in favor of Neumayr's view, but Vermiceraa appears to have arisen in 

 South Germany. 



With regard to the origin of Wsebneroceras and Schlothcimia, ii Beema prob- 

 able from • il evidence that they also arose in the Mediterranean prov- 

 l bowever, geologically incomplete, Bince ii ia probable 

 that > occurred quite as earl} in South Germany. Waehneroceras, 

 ng forms uniting Schlotheira this same 

 - not yel proved to be ol n as Schlotheimia itself, and 

 thia id' iii anachronism \\lii<li requires additional facts i"i its explanation. 

 s i that the Lias t<> the west of the head waters of the Rhine 

 peculiar to the ' I iropean province. W L 



ption* and onfirm tlii* conclusion, since be 'I not men- 



my novel - -one forma, 1 1 | more 



'. 

 ks that there u ilance between the Upper Lias in 



ind fjombardy M - that 



p i 



II p 17 1 



