196 JOURNAL OF THE ARNOLD ARBORETUM [vol. vi 



rimo cinereo. In moist but sandy soil, wooded banks near Troy, on a 

 tributary of Conecuh river/') with mature leaves and young fruit, is in 

 the herbarium of the Arnold Arboretum, as are also a set of Harper's 

 specimens (no. 152, Nov. 6, 1912, "In the 'pocosin' between Troy and 

 Brundidge, Pike County/ 5 ), with mature leaves and separate fruit; and 

 a second collection (no. 154, March 27, 1913), showing young leaves and 

 flowers, and a small photograph of the trunk. There is also in the same 

 collection a series of specimens from the Arkansas stations by Bush, 

 Sargent and Palmer. 



In the original description of Quercus arkansana Sargent says that it 

 is common at the type station but apparently very local. This statement 

 still holds true, although on numerous visits to southwestern Arkansas 

 t luring the past twelve years I have been able to extend its range some- 

 what locally, and it has been found to be much more common than was 

 at first supposed. In addition to the localities on Yellow Creek it has 

 been found along Bridge Creek, Sandy Bois d\\rc Creek and several other 

 small tributaries of Little River and Red River. 



The topography of this small area is peculiar and somewhat remarkable, 

 consisting of low hills and sharp ridges dissected by deep ravines, evidently 

 a relic of the old Tertiary peneplain projecting into the lowlands of the 

 Red River valley. Sterile clays and gravels cover the higher levels of the 

 low plateau and remain on the crests of some of the higher ridges; in the 

 ravines and valleys of the small creeks which traverse it and on the slopes 

 and lower levels along its margins, beds of fine loose sand interstratified 

 with clays and a soft sandstone, passing into marly limestone, with large 

 calcareous oyster shells and other typical Upper Cretaceous fossils, are 

 exposed. In this restricted area, nearly surrounded by the stiff black 

 alluvial lands of the river bottoms, which are subject to frequent overflows 

 and are in places permanently swampy, grow many peculiar plants, con- 

 fined to this environment and some of them now far removed from the 

 general range of their kind. The plants forming these colonies bear every 

 evidence of being relics of a former wider distribution — stragglers left 

 behind in retreat, which have managed to survive in these more favorable 



, beyond which they are unable to extend. Here, as erosion encroaches 

 upon their strongholds, these are gradually becoming more circumscribed, 

 and some of the species inhabiting them perhaps face ultimate extinction, 

 a process and fate that is now being accelerated by the clearing away 

 of the forest from part of the uplands, although this is of little agricultural 

 value. The flora of the lowlands and that of the hills are very different; 

 the majority of the peculiar plants of the latter are found only on the 

 sandy and loamy soils that come to the surface where the later deposits 

 have been removed. Quercus arkansana is practically restricted to these 

 strips, although a few specimens have managed to establish themselves 

 on the gravelly tops of some of the narrow ridges. As Quercus mari- 

 land Ira is found sparingly on the gravelly uplands the two sometimes 



