Download PDF by Kennedy W.J., Cobban W.A.: Aspects of ammonite biology, biogeography and biosratigraphy

By Kennedy W.J., Cobban W.A.

Show description

Read or Download Aspects of ammonite biology, biogeography and biosratigraphy PDF

Best geography books

Read e-book online Thailand (Modern World Nations) PDF

An outline of Thailand's humans, geography, background, executive, financial system, and tradition.

Download e-book for kindle: Irreverent Guide to Chicago by Elizabeth Canning Blackwell

Trying to find a trip advisor that is going the place different courses worry to tread? one who rides roughshod over ad-copy puffery to neatly convey the genuine scoop on a destination's websites and points of interest? one who dares to be sincere, hip, and enjoyable? glance not more. Frommer's Irreverent go back and forth courses are wickedly irreverent, unabashedly sincere, and downright hilarious, and supply an insider's viewpoint on which sights are overvalued vacationer traps and that are the key gemstones that locals love.

Read e-book online Natural Climate Variability and Global Warming: A Holocene PDF

When there's now overwhelming facts that greenhouse-gas toxins is turning into the dominant approach accountable for worldwide warming, it's also transparent that the weather approach varies fairly certainly on diversified time-scales. Predicting the process destiny weather switch for that reason calls for an knowing of the traditional variability of the weather method in addition to the consequences of human-induced swap.

Read e-book online The Geography of Wine: Regions, Terroir and Techniques PDF

Wine has been defined as a window into locations, cultures and occasions. Geographers have studied wine because the time of the early Greeks and Romans, whilst viticulturalists discovered that an analogous grape grown in several geographic areas produced wine with differing olfactory and style features. This publication, in accordance with learn provided to the Wine forte staff of the organization of yankee Geographers, indicates simply how some distance the connection has come because the time of Bacchus and Dionysus.

Extra info for Aspects of ammonite biology, biogeography and biosratigraphy

Example text

TAXONOMIC PROBLEMS Variability. Ammonites, perhaps more than most groups, have suffered extensive taxonomic splitting, and authors have frequently divided intergrading populations into a whole range of species and even genera. Buckman (1892) divided morpho­ logically intergrading series into differing 'species', although admitting they probably belonged to what would now be termed a single biospecies. Spath (1923-1943) made similar statements and commented on the problems of identifying species when large numbers of specimens were available; whole monographs have thus been devoted to descriptions of what are now regarded as but a few species.

Text-fig. 7), a reflection of life habits that changed through ontogeny. AMMONITE Didymoceras nebrascense (Meek and Hayden) TEXT-FIG. cheyennense ECOLOGY 35 Didymoceras cheyennense (Meek and Hayden) 7. A r e c o n s t r u c t i o n o f the C a m p a n i a n n o s t o c e r a t i d h e t e r o m o r p h s Didymoceras ( M e e k a n d H a y d e n ) a n d D. nebrascense ( M e e k a n d H a y d e n ) , b a s e d o n material f r o m the Pierre S h a l e o f C o l o r a d o (after S c o t t a n d C o b b a n 1965).

B) A planktonic or nektonic life habit continued into post-larval life in many taxa, both normally coiled and heteromorph. Washings of sediments deposited many miles from shore often yield abundant juvenile ammonites (A. J. Lloyd, pers. ), and we know of many cases of huge concentrations of juveniles, complete with body chambers, preserved in pelagic deposits. For example we have a collection from the Marias River Shale (Santonian) of north-western Montana, which is a mass of juvenile Baculites codyensis Reeside and Clioscaphites vermiformis (Meek and Hayden).

Download PDF sample

Aspects of ammonite biology, biogeography and biosratigraphy by Kennedy W.J., Cobban W.A.

by David

Rated 4.38 of 5 – based on 46 votes