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Since I've received a copy of the 1909 ed. of 'North American Index Fossils', I'm going to try this question again about the old North Amer. (central/eastern US) divisions of the Cretaceous. Ever since I saw (and diligently copied) a timescale out of the inside cover of an old book (not as old as the 1909 NAIF) when I was in Elem. school, which divided the Cretaceous thus: Laramiean Montanan Coloradoan Dakotan Washitan Fredericksburgian Trinityan Arundelan Patuxentan ...I've been trying to correlate it with the modern divisions. NAIF has this to say abou it: These are pages 652-5 in Volume II. To sum it up, the book quaintly refers to the Lower Cretaceous system as the 'Comanchic', and the Upper Cretaceous as the 'Cretacic', and divides the Comanchic into Trinityan (Lower), Fred...ian (Middle) and Washitan (Upper). The 'Cretacic' is divided into Coloradoan (Lower), Montanan (Middle) and Laramiean (Upper). The Patuxentan and Arundelan are assigned to the Jurassic, but apparently were later added to the Lower Cret. (=Choahuilan?), and the Dakotan was separated from the Coloradoan. Apparently also there is a 1944 ed. of NAIF, and if anyone out there has it, I'd appreciate it if they could tell me what's changed about this since the 1909 ed. Does it confirm the changes I noted, and does it give any more clues about the correlations to the modern (European) stages? If I can find out the modern date estimates for the formations/groups (eg. 'Pierre Series' or 'Niobrara series') that the book divides these units into, I might be able to finally correlate them with the modern ones. Any help there too will be appreciated, Thanks in advance!