130 EXPLORING EXPEDITION FEOM SANTA Ffl 



merited by revolving* lines, two of which, on the body-whorl, become so much larger 

 than the others as to form small carinas Of these two carina 1 , the upper only is seen 

 on the second turn, where it is much reduced in size; and, on those above, it is not 

 distinguishable from the other revolving lines. Marks of growth obscure; aperture 

 unknown; lip extended into a long appendage, the form of which cannot be determined 

 from the specimen examined. 



Length, exclusive of the beak, 0.65 inch; breadth of body- whorl, exclusive of the 

 lip, 0.37 inch; apical angle slightly convex, divergence about 40°. 



The collection contains but a single specimen of this species, and it is unfortunately 

 so firmly imbedded in the hard matrix that it is impossible to work out the labial 

 appendage. It evidently extends out, however, at least as much as 0.55 inch from the 

 axis of the shell; and as its lower margin (which is thickened and a little rellexed) is 

 seen to curve downward, it is probable that there are two salient points to the lip, one 

 of which curves a little downward and the other upward. The lower margin of the lip 

 can be seen to extend out to /of fig. 5, plate 2. 



The body-whorl contracts into the beak below, but the latter is broken from the 

 specimen, so that its form and length cannot be determined. Some eight or nine of the 

 revolving lines maybe counted on the upper turns, and about twenty (including the two 

 carina") on the body-whorl. Half of those on the under side of the body-volution are 

 larger than any of those above the carinas, while between each two of them there are 

 one or two smaller lines. 



In size and general appearance, this species (at least as seen with the lip concealed 

 in the matrix) bears some resemblance to A. Americana, Evans & Shumard (sp.), but 

 has a less-elevated spire, and differs in being destitute of vertical costae. In the latter 

 character, it is more nearly like A. suhhevis, Meek & Hay den, from which it may be 

 readily distinguished by its two revolving carina' on the body-whorl. It may be an 

 Aporrhas, and have to be called Aporrhas Newberry L 



Locality and position. — Same as last. 



CEPHALOPODA. 



Genus BACULITES, Lam. 

 Baculites anceps, var. obtusus.* 



Plate II, figs, 1 a, b, c, d, c, f, g, h. 



B acuities anceps, Lamarck (18-22), An. Sans Vert., vii, (>18.— D'Orbigny (1835), Tab. des Cepb.., 75; and (1840) Paleont. 



Fr. Terr. Crdt., i, 565, plate 139, figs, l, 7. — Roemer, Texas, n»'>: and (1-.V2) Kind, von Texas, 36, ta£ ii, figs. :? 



a, b, c, &c; and of many others. 

 Uaculitcs verlebraHs, Defranco (181G), Diet. Sci. Nat., Supp., iii, 168 ; and of some others, but not of Lamarck. 



The collection under examination contains a number of specimens agreeing 

 almost exactly in size, form, and surface-undulations with those figured under the name 

 of B. anceps by Dr. F. Roemer, in his beautiful work on the Cretaceous rocks and fos- 

 sils of Texas. As Dr. Roemer gives no enlarged figures showing the details of the 

 septa of the Texas specimens, however, we have no means of determining whether or 



"Originally I had not used the variety-name obtumx in connection with this shell ; but I have applied that name to 

 this form in the Upper Missouri Paleontology, now in the press (November 2, 1875), and add it hero in revising flic 

 MS. of this report. 



