656 BROWN AND O'CONNELL THE JURASSIC OF CUBA 



despite the fact that it has been appealed to in the correlation of the 

 Cuban and Mexican faunas. 



The Oxfordian ammonite fauna described by Burckhardt from 

 Durango contains, as we have seen, twenty species, ten of which are 

 identical with or to be compared with European forms, while the other 

 ten are new, but are derivatives from European species. The fauna as 

 a whole belongs unquestionably to the zones of Peltoceras bimammatum 

 (=bicristatum) and P. transversarium, since it contains elements of 

 both. 



Turning to Cuba, we find that the rocks are of similar lithic character, 

 but that the entire series is thinner than it is in Durango. Approxi- 

 mately the same paleontological succession is observed, but a larger num- 

 ber of zones can be recognized and the series includes older divisions of 

 the Jurassic than have yet been found in Mexico. The chief species in 

 common between Cuba and Mexico are : Peris phinctes plicatiloides 

 O'Connell, P. durangensis Burckhardt in the upper Oxfordian; Ocheto- 

 ceras canaliculatum var. burcJchardti O'Connell and 0. mexicanum 

 Burckhardt in the lower Lusitanian zone of Peltoceras transversarium ; 

 Ataxioceras virgulatum (Quenstedt) in the middle Lusitanian zone of 

 Peltoceras bicristatum; Haploceras afr. fialar (Oppel) in the lower Kim- 

 meridgian zone of Streblites tenuilobatus; Simbirskites mexicanus Burck- 

 hardt, Kossmatia victoris Burckhardt, and K. zacatecana Burckhardt in 

 the upper Portlanclian. 



It is impossible to distinguish as a separate unit in Mexico and Cuba 

 the zone of Perisphinctes achilles, which is found to constitute the upper 

 Lusitanian in the French and Argovian Jura. The upper Kimme- 

 ridgian zone of Aulacostephanus pseudomutabilis does not appear to be 

 present either in Cuba or Durango, but it may be represented at Mazapil 

 by the Waagenia beds. During early Portlandian (Portlandian sensu 

 stricto) time there was emergence and erosion in Mexico and probably 

 also in Cuba, for only upper Portlandian strata (Purbeckian) have been 

 found in the two countries. 



Corbel ation of the Jubassic of Cuba and Edbope 



classification of middle and upper jurassic of western cuba and 



southern europe 



When the ammonite fauna of Cuba is compared with that of Europe, 

 there is found to be a sufficiently close resemblance to indicate that both 

 belong to the same geographical province — the Atlantic. A small num- 

 ber of cosmopolitan European species also occur in Cuba, while nearly 



