INTRODUCTION In view of the intermediate position held by the amphibians between air-breathing and water-breathing vertebrates, surprisingly little is known of the external or internal factors regulating respiratory exchange and related circulatory phenomena in these animals. Spurway & Haldane (1953) have suggested that the breathing behaviour in the Amphibia represents the complete expression ...

THE CULTURE OF VERTEBRATE EMBRYOS. By D. A. T. New. New York and London, Academic Press, 1966. 245 pp. $14.00. The purpose of this book, as set forth in the introduction, is to describe available methods for the culture of vertebrate embryos and to note some experiments that have been performed on such embryos. It is intended to benefit both the research scientist and the biology teacher; the u...

The spermatozoa of Gymnophiona show the following autapomorphies: 1) penetration of the distal centriole by the axial fiber; 2) presence of an acrosomal baseplate; 3) presence of an acrosome seat (flattened apical end of nucleus); and 4) absence of juxta-axonemal fibers. The wide separation of the plasma membrane bounding the undulating membrane is here also considered to be apomorphic. Three p...