08 



PLANT LIKE <»F M. A MA MA. 



'Plu- last killiii*,'- fiosl liappcns luiwmi llic middle <>\' l<\'l>nmrv and 

 hitter part of April, on the avcrai,''*'. alMnil tlir Mli or li»tli of March. 

 The iiiaxinmiii tcnipcraturr was in .Inly !<»(; ; the iiiiiiiiiiiiin in Jami- 

 uarv .') .' 'I'lu' course of tlic tcnipcratarc. which has siicli a ])<)t(Mit 

 iiifhiciu-c on phmt ^'•rowlli. is Itcst n'])rcs('ntcd in the foUowinj^ series 

 of tlie absohite and averaj^f minima antl maxima for each iM<^ntli (hir- 

 inir the same ])eriod: 



Serien of maximum and minimujn lemperalurat. 



.xickoi'hii.k forests. 



7hsf-/>ak prnir'u'H. — All over the region, particularly on the highest 

 swells, the drifted clayey loams, sand.s, and pebbles mingle with the 

 soil resulting from the decomposition of the underlying limestone 

 strata, and give rise to light, more or less sandy, loams or heavy cal- 

 careous clay soils, covered with open xerophile forests of Spanish oak, 

 black oak, black jack, post oak, the last predominating, associated 

 with mockernut and pignut hickory. Where the heavy claj' soils 

 prevail, destitute of humus, water-soaked during seasons of rain and 

 leaking to a hard crust during droughts, these so-called post oak prai- 

 ries have been Imt little encroached upon. Under the cover of the 

 brush the gramineous plant formations predominate, while sedge 

 grasses (Cyperaceae) aboiuid in the more shaded and wet situations. 

 For example, EJeocharlx tuhrcnlom^ E. (nmta^ and Oyperua pHeiido- 

 vegetiis^ on the borders of ditches and pools; Care.r triceps^ a very 

 di.stinct southern t3'pe, occurring from South Carolina to central 

 Texas, ))ut not in this State north of the southern edge of the nieta- 

 morphic hills; C. Jurxata^^ C. ohlita^ C. sterills^^ C. lurlda,^ common 

 throughout the Carolinian area; O. ox(/lepls, C. cherokeensh^ C. drhills 

 puhera of a more southern range; together with Ptinlewn, melicariuni^ 

 P. anceps^ and Uniola la-m.^ In drier and more exposed places: 



Sclerin triglomerata ' (abundant) . 

 Alliuvi canadcnse.^ 

 Quamasia esculenta} 

 Lobelia appendiculata. 



The last is a stately perennial of the Louisianian area known from 

 a few localities between South Carolina and northwestern Louisiana. 



^ See footnotes p. 26. 



^ Rarely found north of the Central Pine belt. 



Steironema dliatum. ' 

 Steironema lanceoJutum. 

 Pemtemon hirsutu.i.^ 

 Hibiscus incanus. 



