KLOKA OF 11 IK TKIM'IY FUK.MAI lUN. 341 



In his paper (lescrihing this organism Doctor Knowlton says that llio 

 speciinciis in which it occui-s "came from a srulch on onc^ of tlu^ smaller 

 branches of the Muddy Foi'k of Little Iviver, about (i miles noilheast of 

 ('enterpoint, Howard County. The deposits containing these fossils were 

 referred by Pi'ofessor Hill to the Ti'iuity division of the Lower ("I'etaceous." 

 He was unable to Hx its systematic position, and ti-eated it as a new genus, 

 which h(^ named for Mr. Hill and called the form Pdlcolilllin itrkanmna.'^ 

 Mr. Theo. Holm ])nblished a criticism of Doctor Knowlton's conclusions 

 relatiA-(> to this form,'' but as he did not himself see the specimens his 

 conclusions are entitled to little weight. 



I have now eiuuuerated all the vegetable remains (with the exception 

 of "an undescribed endogenous plant resembling l%quisetnm"' fi'om the 

 Arietina l)eds of the Washita division) that have thus far been reported as 

 having been found in the Comanche series of Texas and Arkansas, and have 

 given a somewhat full account of the history of the discover^' of fossil 

 plants in the Trinity formation. Although the flora has thus far proved 

 meager, it is sufficient to show, even if the fauna and the stratigraphy 

 failed to do so, that the Ti'init>- formation is of Lower Cretaceous age. The 

 al>senc(> of tlicotyledons, however, seems to place it at the very base and 

 give it homotactic rank with the Knoxville and the Kootanie. 



The Twenty-first Annual Report of the United States Geological 

 Survey, Part VU,'' which bears date 1901, l)ut really did not see the light 

 until May, 1902, constitutes Mr. Hill's final contribution to the geology of 

 Texas, and would seem to exhaust the subject. The Black and Grand 

 l)raii'ies occupy most or all of the Cretaceous terranes within the State,, 

 although they are not confined to them, and their description afforded Mr. 

 Hill an opportunity to deal at length with the beds that have chiefly 

 occupied us thus far. He has, however, made scarcely any change in the 

 classification of th(> i-ocks, and adheres to the conclusions last announced. 



"■ Description of a new problematical plant from the Lower Cretaceous of Arkansas, by F. H. Knowlton: 

 Bull. Ton-. Bot. Chill, Vol. XXII, Scptoinlicr, 189.5. pp. 387-390, fif;s. 1-3 on p. 38S. 



'' Kcmiirk.s upon Palcohillia, a prohloriuitii- fossil plant, by Tlieo. Holm: Botanical (iazettc, Vol. XXI 

 April, lS9t,, pp. 207-209, pi. xvii. 



■ Bull. Gcol. ,Soc. Am., Vol. V March 22, 189-1, p. .322, in Geology of parts of Texas, Indian Territory, and 

 Ark»nsa.s adjacent to Red River, by Robert T. Hill: Ibid., pp. 297-.338, pi. xii, xiii. 



'' (Icofiniphy and (ieoloK>- of the Black and Grand Prairies, Texas, with Detailed Dcscription.s of the Creta- 

 ceous F'orniations anil Special Reference to Artesian Watei-s. By Robert T. Hill, Washington, 1<«)1, (itUi pp., 

 71 pl.s. (f) of whicli arc maps), ,S0 text figs. 



