20 TYPE AMMONITES— VII 



dealt with. For the sake of economy in space the plate-numbers are 

 given throughout in arabic numerals. 



Table I (Chronological) contains most detailed information. In it 

 the figured species are arranged under their hemerae in descending 

 (antichronic) order. The ages and hemerae are taken from Vol. V, 

 pp. 71-78, with such additions and modifications as are believed to 

 express the author's own latest views : for purposes of cross-reference, 

 numbers have been allotted to the ages, and letters to the hemerae ; 

 and, for the sake of completeness, ages and hemerae have been included 

 the faunas of which are not figured in this work. 



Square brackets are used in Table I for three purposes : (1) in the 

 case of hemeral names, for equivalent terms used before the eventual 

 name was decided on ; (2) in some cases of altered names, to indicate 

 the earlier name (see Table V for a fuller list) ; (3) to indicate plates 

 replaced by others (see Table on p. 19). 



A " ? " before a name indicates uncertainty as to hemeral position. 

 The abbreviations " G.-t.," " G.-s.-t." and " G.-l.-t." denote respectively 

 genotype (genoholotype), genosyntype and genolectotype (see Vol. I, 

 p. viii). The terms imply genotype-species, and not genotype in the 

 restricted sense explained by the Author in Vol. VI, pp. 5-7. On the 

 plates themselves the term genotype is always used in this restricted 

 sense. 



The word " no v." after a specific name implies that the name dates 

 from the publication of the first plate figuring it. Many other species 

 were first named in the text of this work, but only figured at a later 

 time : their names are followed by, e.g., " S. Buckman 1921," and they 

 are listed in Table VI. 



Table II enables the particulars of any plate to be found by reference 

 to its position in Table I. 



Table III. — The taxonomic position refers to the classification given 

 at the end of Vol. II, with additional families established and other 

 alterations made in later volumes. The Editor has in many cases not 

 ventured to assign a genus a place in the absence of any clear statement 

 of the author's own views. The following gives a summary of the 

 author's scheme as amended, and indicates the abbreviations used in 

 the table : 



IV. PHYLLOCAMPYLI. 



3. Psiloceratacea : Psil [oceratidae]. 

 2. Lytoceratacea : Lyt [oceratidae]. 

 1. Phylloceratacea : Phyll[oceratidae], 



III. SCHISTOCAMPYLI. 



3. Kosmoceratacea : Gowfericeratidae], Gulpelmiceratidae], 

 Par [apat oceratidae] , Kos [moceratidae] . 



2. Stepheoceratacea : Asp[idoceratidae], Atax[ioceratidae]. 

 Mac [rocephalitidae] , Morph [oceratidae] , 

 Pach [yceratidae] , Park [insonidae] , 

 Per [isphinc tidae] , Pro [planulitidae] , 

 Sph [aeroceratidae] , Step [heoceratidae] , 

 Tulptidae], Zig[zagiceratidae]. 



1. Deroceratacea : Der [oceratidae], Dac[tylioceratidae], 

 Ham [matoceratidae] , Polfymorphidae] . 



