HO GEOLOGICAL EEPOBT. [If 135, 136 



tinct impressions of fossils. Nevertheless, Turritella Tippana was recognized, 

 also a Nucula, Yenerieardia, Cytherea ? and Tellina ? — Near Kellum's mill, on 

 E. Ilatehie, on a creek, S. 25, T. 3, R. 5 E., there is a bluff' in which about 20 

 feet of cretaceous strata arc exposed, the upper portion being blue micaceous 

 marl, containing the Owl Creek fossils, the lower more sandy and containing 

 concretions rich in fossils of a character somewhat different ; among them 

 Bacul and a beautiful Pterocera with winged thorns of enormous 



length as compared with the body of the shell. This lower stratum greatly 

 resembles, in character, that found outcropping on Parmeechec (1[118). E. of 

 this locality, in the Dry Creek region, near Jumpertown, shell marls are found in 

 wells, whose palaeontogical character I have not ascertained ; they crop out on 

 the summit of the ridges W. of Blackland (see Tl20) and resemble the Owl 

 Creek marl, but arc very poor in fossils. They appear to form the transition 

 from the Ripley Group to the Rotten Limestone. The same is probably true of 

 an outcrop on the head of Old Town Creek, at the E. foot of the Pontotoc 

 Pidge, on S. 16, T. 8, P, 4 E. 



135. The ridges S. of Wilhite's Creek, in Tippah, in the S. portion of T. 6, 

 P. 4. E., known as " The Buncombes," may be considered as the N. end of the 

 Pontotoc Ridge proper. The general geological character of this ridge has 

 already been described ; from the Tippah line to its termination N. E. of 

 Houston, its hillsides and ravines exhibit numerous outcrops, both of " bored 

 limestone" and of blue marl, generally interstratified with irregular limestone 

 ledges, and containing the leading fossils of the Owl Creek marl, with many 

 local variations and additions. While in some localities the uppermost limestone 

 retains the great hardness of the Turritella limestone of Tippah (as on 

 Labatubby, S. 36, T. 8 P. 2, where it appears in a solid ledge about 30 feet in 

 thickness, and Mr. Daggett's, S. 32, T. 10, R. 36 — both on the edge of the 

 Flatwoods), at others it appears as a yellowish white, sandy, soft calcareous 

 mass, which very frequently forms the bald prairie hilltops of the Ridge. 

 Characteristic outcrops of this material may be seen at the mouth, and in 

 numerous spots along the bluff of King's Creek, and of Okonatyhatchie ; as also 

 near Redland, overlying the bored limestone, into which it show's frequent 

 transitions, by partial induration within its mass. 



136. Where soft strata intervene between beds of rock comparatively solid, 

 the soft stratum is sometimes washed away, so as to form caves, etc. Thus, on 

 S. 25, T. 7, P. 2 E., a branch of King's Creek flows out of a cave between two 

 beds of sandy limestone, and is spanned, 15 yards from the mouth of the cave, 

 by a natural bridge 18 feet long, and about 5 above the level of the branch ; it io 

 14 feet wide at one end, 5 at the other, and the ledge 2 to 2% feet thick. The 

 cave at its mouth is about 9 feet wide by 6 high, but rapidly contracts, so as to 

 become little more than a channel for the water ; then again it expands into a 

 long chamber of about the dimensions at the mouth, whose roof is covered with 

 short stalactites. Subsequently it contracts again, forks, and cannot be followed 

 up for more than about 120 yards, winding about, but generally in a S.S. W. 

 •direction. About 70 yards S. E. from the mouth of the cave, there are several 



