51943. Shrock, R. R. and Twenhofel, W. H.   Principles of Invertebrate Paleontology.   McGraw-Hill Book Company, Inc, 1953, Series in Geology, 816 pages with illustrations.   Hardbound, binding a little cocked, other minor signs of use, text in very good condition.    $30.00

8584. Newman, K. R.   Upper Cretaceous-Paleocene Guide Palynomorphs from Northwestern Colorado.   University of Colorado Museum, 1965, Series in Geology, 2 : 1-21, 5 figures and 1 plate.   Printed wraps, minor previous owner marks, usual signs of age and use, text in very good condition.    $11.00

7212. Valetine, J. W. et al.   Phanerozoic Diversity Patterns: Profiles in Macroevolution.   Princeton University Press, 1985, Series in Geology and Paleontology, 424 pages and multiple text figures.   Hardbound, dust jacket, very good to near fine condition.    $37.00