The Invertebrate Fauna of the Uitenhage Series. 61 



in detail below have already been briefly noticed in the second section 

 of this paper, in so far as it seemed necessary to draw attention to 

 their significance in reference to the question of geological age : the 

 names of these, and the remainder of the invertebrate fossils of the 

 Uitenhage Series which have hitherto been recorded, are brought 

 together in the supplementary list and brief accompanying notes 

 with which the present section of this memoir concludes. 



In those few instances in which Uitenhage forms are referred to 

 European species, I have refrained from burdening the subjoined 

 accounts with full synonymic lists, but have given a reference to the 

 original description and, where possible, to a recent work in which 

 fuller guidance to the literature of the species may be obtained. 

 Throughout the following pages, however, nomenclatural references 

 are restricted to those works which contain such information as to 

 insure, in my belief, the truly synonymic value of the citations. 



In the description of the Gasteropoda a conventional orientation 

 is employed for the sake of clearness, and when use is made of the 

 terms "above" and "below" in this connection it is assumed that 

 the specimen be held with the apex directed vertically upwards. 

 The terms " nepionic " and " neanic," occasionally employed with 

 reference to the young or immature stages in some of the lamelli- 

 branchs described below, are so well known and so frequently used 

 as to call for no explanation here.* 



For an account of the available geological information in connec- 

 tion with the occurrence of the specimens obtained in 1900 reference 

 should of course be made to the Eeport by Messrs. Eogers and 

 Schwarz,f but this may be supplemented by a brief note contained 

 in a letter written to me by Mr. Eogers, to the following effect : 

 "The specimens from Dunbrodie and Blue Cliff are from the lower 

 beds of the Uitenhage Series, those from the Clay Pit near Eawson 

 Bridge from the lowest marine beds in the Zwartkop's Eiver section. 

 Those from the Grass Eidge, Uitenhage, and from the kloofs near 

 Eed House and Picnic Bush belong to the highest beds we found, 

 and the specimens from the Graaff-Eeinet railway section and those 

 from the main line up-side of Eawson Bridge are from the middle 

 portion of the marine beds." I am informed that the collection 

 obtained at Coega by Miss Wilman was made at a locality on the 

 farm of that name, though outside the river valley, while the label 

 "Coega Eiver" refers to a section in the river valley on the same 

 farm, but probably on a rather lower horizon in the Marine Beds. 



* See Hyatt (1) ; Jackson (1), p. 293 ; Buckman and Bather (1) ; Hyatt (2), p. 94. 

 t Kogers and Schwarz (1) ; also Rogers (1), pp. 281-292. 



