File:Geological magazine (1914) (14762278014).jpg

Identifier: geologicalmagazi611914wood (find matches)
Title: Geological magazine
Year: 1864 (1860s)
Authors: Woodward, Henry, 1832-1921
Subjects: Geology
Publisher: London (etc.) Cambridge University Press
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Smithsonian Libraries

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
reas strongly oval and usuallywith a flattened and straight upper end, average length 28 to 33 mm.and breadth 18 to 2 mm.; side walls typically thin, especially at theupper end.; in those zooecia, almost exclusively the very early ones,which have no ocecium there may be observed under high magnificationa pair of projecting tubules on the side wall at the extreme upperend, and in most zocecia traces of one or even two pairs of pores canbe seen in the side walls a little lower down, but these featuresrequire a much higher magnification than twelve diameters for makingthem apparent, and I think they are only relics of discardedappendages. Ocecia almost invariably present after the earliest stages, relativelyrather large, globular, and slightly bottle-necked, rarely preserved,the specimen shown by Fig. 6 being most exceptional. Avicularia of two kinds: (1) The characteristic accessory type,always present, bluntly triangular, with a slightly rounded lower end. Geol. Mag., 1914. Plate XXVI.
Text Appearing After Image:
B. M. Brydone, Photo. Remrosf, CoUo. Chalk Polyzoa, B. M. S. Watson—Reptilian Femur from Scotland. 347 the aperture divided by the crossbar into distinctly unequalcompartments, but not definitely mandibular. (2) Vicarious, occurringchiefly at the beginning of a new row of zocecia, but sometimes alsoin an already established row ; they are of the hourglass type withthe expanded upper part of the area almost circulai, but the lowerpart narrow and with nearly upright side walls, giving a generaloutline resembling that of a puff-ball; the transverse bar (which wasprobably always present in the hourglass type) is placed close to thelower end of the area. This species occurs in, and seems to monopolize as far as its groupis concerned, the zones of 0. pilula and A. qtcadratiis in Hants andSussex. It is clearly ancestral to M. Griffithi. Membranipok.i GRIFFITHI, mihi.^ (PI. XXVI, Figs. 7, 8.) I take the opportunity of giving photographic figures of thisspecies to assist comparison and corre

Note About Images