Details - The ultrastructure of five common Pennsylvanian pleurotomarian gastropod species of eastern United States

The ultrastructure of five common Pennsylvanian pleurotomarian gastropod species of eastern United States

Title

The ultrastructure of five common Pennsylvanian pleurotomarian gastropod species of eastern United States

Title Variants

Alternative: Pleurotomarian gastropods

Related Titles

Series: American Museum novitates, no. 2501

By

Batten, Roger Lyman

Type

Book

Material

Published material

Publication info

New York, N.Y, American Museum of Natural History, [1972]

Notes

Title from caption.

"August 21, 1972."

"The shell ultrastructure of five pleurotomarian gastropod species from the Pennsylvanian is described and and variation discussed; in addition, some observations are made of three bellerophontid species. Two thin outer shell layers previously unknown are analyzed. The outermost of these is fibrous and about 10 [microns] thick; it appears to be the only one that is actually involved in the topographic expression of growth. The two principal layers of the species studied are an outer complex prismatic layer and a thicker inner nacreous layer. There is an innermost complex prismatic unit which is variable in development and may be absent in some species. Several types of pallial myostracum are present in all species examined. The importance of shell structure in elucidating the origin and phylogeny of molluscan groups is briefly discussed. Most variation of ultrastructure appears to occur within or between species and is quite conservative between larger taxonomic units"--P. [1].