MAZATLAN UNIVALVES 485 



not easily located elsewhere, it is here used in the enlarged 

 sense. The present species approaches very nearly to E. costu- 

 laris, Lam., E. gibbosus, Rve., and E. Californicus, A. Ad. It 

 is known at once from Cnma costata by the roundness of the 

 ribs, want of keel, and the greater narrowing and recurving of 

 the canal. Although apparently of sedentary habits, not 

 eating away obstructions in its shell close to the columella, it is 

 remarkably free from the incrustations which usually cover C. 

 costata. The form of the canal often irregularly approaches 

 Cassis. The operculum closely resembles that of Cuma costata, 

 differing in being somewhat more elongated, the pale margin 

 not so distinctly marked off, and the surface rougher. The 

 largest sp. measures long. 1*12, long. spir. '54, lat. ' 67 div. 55. 



A broad sp. '84, "38, '65, 65. 



The most depressed sp. '57, *22, "56, 80. 

 Hob. Mazatlan ; rare ; IS pool Col. 



Tablet 2278 contains 3 sp. depressed form. 2279, 3 do. nor- 

 mal shape. 2280, 3 do. acuminated. In the largest, a portion 

 of the canaliferous rib remains, not eaten away, overhanging 

 the labium. 2281, 4 sp. shewing the labrurn at different stages 

 of the costae. 2282, 4 sp. with 5, 6, 7 and 8 ribs respectively. 

 2283, 2 sp. shewing extremes of sculpture. 2284, 2 sp. with 

 opercula. 2285, 2 sp. with adhesions. 2286, 2 sp. mended 

 after fracture : one has formed a second canal ; the other has 

 twisted it back at an angle of 110. 



GENUS VITULAEIA, Swains. 



Treatise, p. 297, 1840. H. fy A. Ad. (inter Murices,operc. ign.) 

 Gen. vol. i. p. 74. Shell with very irregular varices ; oper- 

 culum Purpuroid. 



^~ 612. VITULARIA SALEBEOSA, King. 



Murex salebrosus, King, Zool. Jbwrn. vol. v. p. 347. Sow. 

 Conch. III. pi. 65, f. 48.Kien. Icon. Conch, p. 121, pi. 47, 

 f. 1. Lam. An. s. Vert. vol. ix. p. 613, no. 84. Rue. Conch. 

 Ic. pi. 21, f. 98. Mice, in Zeit.f. Mai. 1850, p. 187, no. 68. 

 C. B. Ad. Pan. Shells, p. 125, no. 142. 



Fusus salebrosus, Forbes, Proc. Zool. Soc. 1850, p. 274. 



Murex vitulinus, Gray, Zool. Seech. Voy. pi. 33, f . 4, 6 ; [non 

 Lam. loc. cit. p. 595, no. 53:= Murex purpura (Chemn.) 

 Desk, in nota: = M. miliaris, Gmel. Dillw. Wood.'] 



