The Invertebrate Fauna of the Uitenhage Series. 185 



the results and requirements of modern work, and that a division 

 into a number of genera or sub-genera had become necessary.- If 

 we were to ascribe to the name Holcostephaims the broad signification 

 allowed by Neumayr, Zittel, and others, it would certainly be con- 

 venient to use the name Astieria to denote one of several sub-genera, 

 were this procedure not contrary to the recommendations of the 

 International Zoological Congress. t It will be more correct, as 

 Lemoine has pointed out, to restrict the name Holcostephanus to 

 that portion of the genus, as originally conceived, which is typified 

 by H. astierianus, and apply it in place of Astieria.l 



The separation of Spiticeras from Pavlow's Astieria, as proposed 

 by V. Uhlig and F. Suess, appears to be a well-founded step in the 

 recognition of further divisions within the broadly conceived genus 

 Holcostephanus. Holcostephanus , sensu stricto (= Astieria Pavlow, 

 emend. V. Uhlig and F. Suess) thus becomes a group having very 

 narrow limits, and some division of opinion is likely to exist con- 

 cerning the question of its generic or sub-generic value. This at 

 present must remain a matter for individual judgment, and in view 

 of our rapidly growing knowledge and the other causes which con- 

 tribute to the present instability of ammonite-classification, it is a 

 question of comparatively subordinate importance. For the purposes 

 of the present work the name will be employed in a generic sense > 

 as the equivalent of the restricted Astieria of Uhlig and F. Suess. 



It is unfortunate that the specimens of Holcostephanus obtained 

 from the rocks of the Uitenhage Series are usually in a state of 

 preservation unfavourable for exhaustive study. Thus, in no case 

 has it been possible to ascertain the true course of the lobe-line, while 

 evidence regarding the form of the body-chamber and mouth aperture 

 is likewise still scanty. We must also look to further collecting to 

 furnish materials for a study of individual development in the various 

 forms represented, and it is clear that there is much to be added in 

 order to supplement the following imperfect account of this interesting 

 assemblage. There can be no doubt, however, that the characters of 

 shape and ornament displayed by the available specimens suffice to 

 enable us to read aright the relationships of these forms, though 

 perhaps not always with the precision that might be desired. 



It may be pointed out that in the diagnosis of Astieria given in 

 Uhlig' s monograph on the Fauna of the Spiti Shales a sentence 



* Pavlow and Lamplugh (1), pp. 471, 491 (113, 133 of authors' copy). 

 f Regies Internationales de la Nomenclature Zoologique adoptees par les Congres 

 Internationaux de Zoologie ; articles 9, 25, 29. Paris, 1905. 



} Lemoine (1), p. 181. Uhlig (4), p. 86. 



