Springer, Victor G. Pacific Plate Biogeography, with Special Reference to Shorefishes. Smithsonian Contributions to Zoology, number 367, 182 pages, 65 figures, 5 tables, 1982.—It is the thesis of this study that the Pacific lithospheric plate (Pacific Plate) forms a major subunit of the Indo-Pacific biogeographic region. This thesis is defended on two primary grounds: the sharp decrease in numbers of taxa as one proceeds eastward across the western margin of the Pacific Plate, and the presence of a high degree of endemism on the Plate. The complex geotectonic history of the Plate and adjacent plate margins is discussed and the vicariance scenarios that produced the three main types of endemism (widely distributed Plate endemism, endemism restricted to a limited region on the Plate, and endemism restricted to single islands or island groups) are hypothesized. Anecdotal discussions of the distributions of 179 shorefish family groups are presented, as well as discussions of the distributions of selected terrestrial and marine taxa of other organisms. Particular attention is given to presumed erroneous or exceptional distributions of fishes on the Pacific Plate, including, but not limited to, north-south disjunct distributions, Hawaiian Islands' exceptional distributions, and distributions involving the Caroline Islands, which serve as stepping stones for dispersal onto the Pacific Plate. OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Smithsonian Year. SERIES COVER DESIGN: The coral Montastrea cavemosa (Linnaeus). Library of Congress Cataloging in Publication Data Springer, Victor Gruschka, 1928Pacific Plate biogeography, with special reference to shorefishes. (Smithsonian contributions to zoology ; no. 367) Bibliography: p. Supt. of Docs, no.: SI 1.27:367 1. Fishes—Indo-Pacific Region—Geographical distribution. 2. Biogeography—Indo-Pacific Region. 3. Fishes—Pacific Ocean—Geographical distribution. 4. Geology—Pacific Ocean. I. Title. II. Title: Shorefishes. III. Series. QL1.S54 no. 367 [QL623.98] 591s [591.92'5] 82-600146 AACR2

Pacific Plate biogeography, with special reference to shorefishes

Etude menee en vue de quantifier les pertes en poissons dues a la predation par cette meduse (prelevements effectues en dec. 1981 dans le Golfe du Mexique au large de Pensacole, dans ce meme Golfe, en fev. 1982 au large de Galveston et en mai 82 dans la Mer des Sargasses)

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Predation on fish larvae by Physalia physalis, the Portuguese man of war

Publisher Summary
Antisymmetry is a peculiar kind of variation whose evolutionary significance is surprisingly unappreciated, no doubt in part because the term seems odd and foreboding. Antisymmetry refers to the condition where right-sided and left-sided—or dextral and sinistral—forms are equally common within a species, as seen in the major claws of lobsters and male fiddler crabs, the side to which the upper mandible crosses in most crossbill finches, or the spiral orientation of palm-tree trunks. Antisymmetry can therefore only be confirmed by examining multiple individuals or multiple parts on an individual. Antisymmetry is a particularly important kind of phenotypic variation because, with very few exceptions, the direction of asymmetry is not inherited. In other words, although the phenotype “asymmetric” is clearly heritable, the conspicuous and readily observable phenotype “right-handed” is not. Such a claim can rarely be made for other kinds of variation. This lack of a genetic basis to a readily observable phenotype lends antisymmetry its great significance. Because direction of asymmetry is not inherited, each evolutionary transition from an antisymmetric ancestor to a directionally asymmetric descendent represents an example of the seemingly heretical, neo-Lamarckian phenomenon of genetic assimilation: a conspicuous phenotype with no heritable basis arising evolutionarily before that phenotype comes under genetic control.

CHAPTER 16 – Antisymmetry

Die süsswassermeduse Craspedacusta sowerbii Lankester in monographischer darstellung

The Portuguese man-of-war: Gone with the wind

THE Portuguese man-of-war (Physalia) occurs in two forms which are mirror images of one another but otherwise identical. Under the influence of the wind, one form (left-handed) moves to the right of the downward direction, the other (right-handed) to the left.

Dimorphism in the Portuguese Man-of-War

IN NATURE for Jan. 12, Prof. Hickson has recorded freshwater medusae and their polyps from Mr. V. B. Poulton's aquarium at Boscombe. Afterwards these were assigned to Craspedacusta sowerbii after comparison with drawings made at the British Museum of polyp stages of that species found last summer on Pandanus roots in the Victoria regia tank of the Royal Botanic Society and exhibited at a meeting of the Zoological Society.

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A. K. Totton

Papers

Dimorphism in the Portuguese Man-of-War

Freshwater Medusæ in England