372 UNITED STATES GEOLOGICAL SURVEY OF THE TERRITORIES. 



last. Again, its aperture is proportionally broader than in the typical form, 

 being nearly quite as wide as high, instead of higher than wide. 



I have yet only seen one specimen of this form showing the aperture 

 and inner lip. This one has the third or lower carina of the body-volution 

 obscurely developed, and the nodes on the other two principal ones more 

 numerous and more closely arranged than those on that represented by our 

 figure 10, c, and its columella more oblique than it is restored in that figure; 

 but no one would for a moment think of separating it, even as a variety, from 

 that shell. In this specimen, which is larger than that represented by 

 figure 10 c, the inner lip, although not entire, certainly seems to have 

 been decidedly more free from the columella, along its outer edge opposite 

 the middle of the aperture, than that of the more ventricose form. 



Until the relations of this form to P. Bairdi can be determined more 

 satisfactorily from the stud}* of a better series of specimens, I would propose 

 to range it under a distinct name as a variety of that shell. 



Locality and position. — Same as last. 



Genus FUSUS, Bruguiere.* 



Si/non. — Fusus (sp.), Kleiu, Martini, Sehroter, and other pre-Linnsean authors. 



Fusus, Bruguiere (1789), Encyc. Me"th., I, xv.— Bolten (1789), Mus. Bolt. (ed. 2a, 1819, 83).— 

 Lamarck (1799), Prodr., 73; and (1801) Syst. An., 82; also (1822) Hist, VII, 121.— 

 Deshayes (1830), Encyc. Me'th., Ill, 174.— Keeve (1841), Proceed. Zool. Soc, 76 ; also 

 of numerous later authors, with various limits (hut not of Humphrey, 1797). 



Coins, Humphrey (1797), Mus. Col., 35. 



Syrinx, Bolten (1799), Mus. Bolt. (ed.2a, 1819,85). 



Fiisitms, Eaf. (1815), Anal. Nat., 145. 



Sinistrality H. and A. Adams (1853), Genera Recent Moll., I, 79 (as a subgenus). 



Etym. — Ftisitx, a spindle. 

 Exam}). — Murex coins, Liunasus 



Shell fusiform; axis imperforate; spire many-whorled, acuminate, and 

 produced to more or less nearly (rarely beyond) the length of the canal and 

 body-volution ; whorls angular, carinate, nodose, or provided with folds, costas 

 or spines, or merely evenly convex ; canal slender, and generally long and 

 straight; aperture oval, or more or less rhombic; columella without plaits or 

 folds ; outer lip simple, and often striate or sulcate within ; surface generally 

 with revolving markings. 



Probably no other generic name in the whole range of conchological 

 science has been more indefinitely used than this, both by palaeontologists 



* The genus Fusus is very generally referred to the Hurividw, but Dr. Stimpsou some time back 

 discovered that a recent typical species of the genus has decidedly the dentition of the Fasciolariida: 



