128 PHYLOGENY OF FUSUS AND ITS ALLIES. 



These species of Tnrbinella run in a general way through the same 

 series of variations as do those of Claz'ilithcs, but no shoulder has been 

 observed. 



Clavilithes in the North German Oligocene. 



CLAVILITHES EGREGIUS (Beyrich). 



(Plate XIII, fig. 12.) 



1856. Fusus cgregius Beyrich, Zeitsch. Deutsch. Geol. Gesell., Bd. VIII, p. 78, 



pi. 22, figs. 1-5. 

 1889. Fusus (Clavella) cgregius v. Koenen, Norddeutsches Unter-Oligocan, Lief. 



I, p. 206, pi. 20, fig. II. 



A single specimen of this species has been seen in which the proto- 

 conch and early whorls of the conch have been broken away. None 

 of the remaining whorls are ribbed, and apparently none of the earlier 

 whorls were. The first four whorls are spirally striate, the first two 

 globular with simple spirals, the next two with intercalated spirals and 

 the form turbinate, /. c. the greater portion below the suture being flat, 

 not convex. The lower part is abruptly deflected inward. The last 

 whorl is smooth. Beyrich figures several large and fine specimens of 

 this species, which rival in size the Parisian forms, without, however, 

 equalling the British. The last whorls remain smooth and of a some- 

 what rounded contour, the turbinate aspect of the young being lost. 

 This and the absence of the shelf show that this species has not passed 

 beyond the conjiiiictus stage. The rugosiu stage is dropped altogether, 

 the species beginning with the damcriaccnsis stage. The protoconch 

 is papillose but the terminal portion seems to be somewhat coarser than 

 that of the normal Parisian forms. 



The turbinate aspect of the young is caused by the fact that the 

 later whorls embrace the earlier ones up to the middle. 



Localities: Wolmirsleben (M. C. Z. 11 14) ; Westeregeln, Atzendorf 

 and Welsleben, North Germany (Beyrich) ; Lattorf, Calbe, Atzendorf, 

 Unseburg, Welsleben, Westeregeln, Osterweddingen, Helmstadt ; 

 Lethen; North Germany, Also Brockenhurst Hants. England (von 

 Koenen). 



American Si^ecies of Clan-ilithes. 



The American (Gulf Coast) species which are generally referred to 

 the genus Clavilithes offer a surprising parallel to those of the Paris 

 Basin. There are, however, distinct features which persist throughout 

 the entire series and which might perhaps be considered as sufficient to 

 demand separation of this series under a distinct generic name. The 

 chief of these features are the loose coiling, the broad ribs of the pre- 

 ephebic stages, and the character of the protoconch. The latter is very 

 irregular and when perfect presents a slight upward projecting apex, 

 very different from that of the Paris Basin species which has a termi- 

 nation consisting of a minute naticoid whorl with rounded apical end. 

 The apical whorls of the American species are furthermore laterally 



