— 42 — 



four fine ones between each, and twelve to fifteen others below angle 

 pass around the canal. (The shells being imbedded in rock the exact 

 number of vertical ribs cannot be distinctly seen, whether seven or 

 eight, and the outer lip is too much broken to see the form of the sinus, 

 but it must be very shallow.) Mouth very narrow, sharp above, 

 widest at angle of lip, below curving to the left, gradually forming the 

 canal. Columella with four plaits at middle, the upper one strongest. 

 Length, 0.48 inch; breadth, 0.09; mouth, 0.14 long, 0.03 wide; canal, 0.10 

 long. 



The figure is twice the natural size of the one specimen found at 

 Marysville Buttes by Mr. Watts. This is a decidedly different shell 

 from the two species figured and described by Mr. Gabb, both of which 

 were also found in Santa Ana Mountains, Orange County, by Dr. 

 Bowers, but in a very poor condition. 



Cancellaria irelaniana n. sp. (PI. I, Fig. 5.) 



Shell oblong fusiform; spire of eight whorls, the first three nuclear, 

 smooth, conical; fourth with nine prominent vertical ribs, abruptly 

 truncate at sutures, and continuing thus on next three whorls, but on 

 eighth whorl becoming conical, tubercles at posterior margins, more 

 distinct on body-whorl, the ribs disappearing. The three anterior 

 whorls show strong vertical lines of growth, or irregular sculpture, 

 which above the tubercles is crossed by three or four revolving raised 

 lines. (Outer lip broken off" for about half an inch.) Columella with 

 four ver}^ strong and three fainter oblique folds (or ribs). Length, 

 about 1.75 inch; breadth, 0.75; mouth, 0.87; width, (?). 



Only one specimen found at Marysville Buttes by Mr. Watts. This 

 shell is nearer to the sub-genus Narona than to any of the allied forms, 

 and in its spire much resembles the species living on our coast, 

 C. {N.) cooperi Gabb. Though Mr. Gabb described a Tertiary species 

 as C. vetusta, thus suggesting its absence from the Cretaceous strata, 

 we have here a j^roof of its presence in the Eocene or Cret. B strata. 



Genus, Ancilla Lamarck. Oliverato, nov. sub-genus. 



Sub-Generic Characters. — Young shell resembling an Oliva, with three 

 nuclear turbinate whorls, the next three rapidly enlarging, forming a 

 conical spire, Avhich becomes nearly buried by callus in the adult; the 

 seventh whorl as in young Cyprea, etc. The eighth whorl, instead of 

 growing longer, increases chiefly by enveloping and thickening the 

 body of the shell, the deposit of callus forming two thickened layers 

 on the sides of shell, extending toward the middle of back as the 

 animal grows older, but rarely meeting, or only as a thinner layer in 

 the middle, and burying half the spire in its growth. Section of shell 

 thus forms an obtuse triangle as in some Cypreas (one specimen only 



