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SCIENCE 



[N. S. Vol. XXV. No. 650 



adopted, the Spanish name may be given up; 

 but that in the meantime cuesta is much 

 better than no name at all. It will now be 

 interesting to note what acceptance is gained, 

 especially in England, by wold and vale in 

 the restricted sense proposed by Veatch; and 

 to know how many American physiographers 

 will say ' Chunnenugga wold ' and ' Winne- 

 bago vale ' for the cuesta of southern Alabama 

 and the inner lowland of eastern Wisconsin. 

 ' Wold,' like ' forest,' originally meaning wild- 

 land, but not necessarily wood-land, is taken 

 from eastern England, where it names the 

 lop-sided ridge of chalk which ends at Elam- 

 boro head; but the chalk cuesta elsewhere in 

 England has other names, such as Chiltern 

 ' Hills,' near Oxford, and the North and South 

 ' downs,' on either side of the eroded lowland 

 of the Weald (another form of wold) : and 

 ' vale ' is used in England not only for low- 

 lands of the kind here considered, but also 

 for the Vale of Eden, eroded on a faulted mass 

 next west of the Pennine escarpment ; and for 

 the Vale of Pewsey, an anticlinal valley. It 

 is perhaps as doubtful whether English physi- 

 ographers will be content to use these semi- 

 poetic terms in the limited systematic sense 

 proposed by Veatch, as whether Spanish 

 physiographers (if such there be) will be satis- 

 fied with the foreign use of cuesta for a low 

 lop-sided ridge. 



W. M. D. 



SOUTHERN ARKANSAS AND NORTHERN LOUISIANA 



The inner part of the coastal plain in the 

 Gulf States is well known to be a hilly dis- 

 trict, but it is not often that one meets specific 

 and systematic accounts of its topographic 

 features. A few pages of welcome informa- 

 tion on this matter are found in a recent 

 report by A. C. Veatch (' Geology and Under- 

 ground Water Eesources of Northern Louisi- 

 ana and Southern Arkansas,' prof, paper 46, 

 TJ. S. Geol. Survey, 1906, 14^16), where the 

 hill lands between the broad flood plains of 

 the Mississippi, Ouachita, Red and Sabine 

 rivers are described as traversed (ENE- 

 WSW) by several ' ranges of hills, which are 

 more or less persistent for many miles and 

 which follow the general strike of the forma- 



tions producing them.' The ranges and the. 

 strike valleys between them are called wolds 

 and vales, according to the terminology re- 

 ferred to in the preceding note. The Kisat- 

 chie wold, formed on the Catahoula (Grand 

 Gulf) formation in northwestern Louisiana, is 

 perhaps the most important. According to 

 McGee it is continued southeastward through 

 the state of Mississippi as the ' Grand Gulf 

 hill land'; and it is due to this wold-making 

 formation that the Mississippi flood plain is 

 narrowed and its enclosing bluffs are increased 

 in height near Natchez (' Lafayette Forma- 

 tion,' 12th Ann. Eep. F. S. Geol. Survey, 1891, 

 366-370). Sulphur wold, formed on the sandy 

 beds of the lower Eocene, extends from south- 

 western Arkansas into Texas: between its in- 

 ner face and the next (Saratoga) wold, farther 

 inland, is a vale along which a main railway 

 line runs from Little Eock. Sulphur wold 

 would appear to be the trans-Mississippi repre- 

 sentative of what is known in Alabama as the 

 Chunnenugga ridge (best described by E. A. 

 Smith, Geol. Surv., Alabama, Eep. for 1881-2, 

 p. 273), and in Mississippi as the ' Lignitic 

 hill lands ' (see McGee, as above) . The wolds, 

 cuestas or hill lands of Arkansas and 

 Louisiana are not continuous upland belts, but 

 are maturely dissected into gentle hills and 

 open valleys by consequent and insequent 

 streams (subsequent streams are poorly de- 

 veloped), with a relief of 100 or 200 feet. 



The peculiar shallow lakes which once oc- 

 cupied the valleys lateral to that of the Eed 

 river of Louisiana are described with care (pp. 

 59-64). The explanation which attributes 

 them to obstruction by normal though rapid 

 aggradation of the main-river flood-plain is 

 shown to be in error. They are due to the ob- 

 struction of the main river by its ' raft,' or 

 jam of fallen trees. The raft grew by gradual 

 addition to its upper end, while its down- 

 stream end slowly decayed and drifted away. 

 As one tributary stream after another was 

 thus obstructed, a shallow lake rose in the 

 lateral valleys. The raft has been artificially 

 removed (1873) by cutting away the tree 

 trunks; and since then the river has lowered 

 its bed and the lakes have shrunli or disap- 

 peared. They are given too great number and 



