PHYLOGENY OF FUSUS AND ITS ALLIES. II9 



In this respect, as well as appearance generally, it recalls the typical 

 r.ritish species C. solanderi, but since C. macrospira was described 

 from imperfect material its identity with the British species is not 

 proved. Should more ])erfect material show this identity, Cossmann's 

 specific name will of course supersede mine. 



Cossmann states that the young whorls are ornamented by ribs and 

 spirals, but that these have disappeared on the hfth whorl before the 

 last, the final ones being smooth. 



Two specimens from the Paris Basin (M. C. Z. 27761), though 

 worn, show the characters of this species. The earliest whorls are 

 broken away and the characters of the youngest stages is, therefore, 

 not determinable. The final portions of the last whorl have a scalaris- 

 like projection of the shelf. 



This species may have been derived from C. suhscalaris by flat- 

 tening of the upper portion of the wdiorls. 



Localities: Paris Basin (M. C. Z. 27761). 



Horizon: Upper Eocene (Cossmann). 



CLAVILITHES MAXIMUS (Deshayes). 



1S24. Fusus maximus Deshayes, Coq. Env. Paris, p. 526, pi. 71, figs. 11-12. 



1850. Fusus maximus Deshayes, Rouault, Foss. Eoc. Env. Pau, T. Ill, pt. 2, p.. 



489, pi. 17, fig. 8. 

 1889. Clavilithcs maximus (Deshayes) Cossmann, Cat. Coq. Eoc. Paris, T. 4,. 



p. 177. 



This very large and robust species from the middle Eocene o£ 

 Chaumont, etc., is of somewhat uncertain affinities. 



According to Rouault, Deshayes' figure does not agree with the 

 description given by that author, the illustrated specimen being doubt- 

 less a very old and worn individual. The shell figured by Rouault is 

 stated to have in the neighborhood of fourteen whorls, the last of which 

 have a strong shelf. Only six whorls are shown, the top being broken 

 away, and there probably were not above three or four more. The ribs 

 are broad, separated by less than their width, and they persist into 

 the penultimate whorl as faint wrinkles or undulations. Intercalated 

 spirals are shown on the earliest preserved whorls. The shelf begins 

 on the last of the ribbed whorls, is well developed and horizontal. On 

 the preceding whorls it is replaced by a subsutural band. The whorls 

 become cylindrical after the appearance of the shelf, and the spirals 

 persist, though faintly, onto the otherwise smooth body-whorl. They 

 are strong on the spindle. The total length of the shell figured by 

 Rouault nmst have been between five and si.x inches. The shell 

 resembles the British C. solanderi, but the ribbed whorls continue 

 longer, the sides are parallel to the axis instead of converging; the 

 shelf is horizontal instead of sloping inward, and the spirals are 

 persistent, especially on the spindle. 



