MOROCCO. 361 



Jiniits the iiortlioni hoi'izoii of .Miu-rakesli ; tlie I)j. Aclular. (lie I)J. 

 Karra, and similar small mountain ran<i:os, present phenomena recall- 

 ing those of the Tannus in (lermany or (he Siei-ra <le Alcudiad, and 

 other mountains of the Spanish table-land. The similarity between 

 these primitive mountains of Spain and those of Morocco is in general 

 ^•ory great, especially in so far as the older formations were overlaid 

 by more recent deposits, consisting of strata entirely horizontal and 

 still undisturbed, but merely elevated. The older formations show 

 through the ret-ent deposits onl}^ where rocks capable of more resist- 

 ance jutted up, or where the recent formations yielded either to the 

 (MUM'getic erosion and demulation produced by running water in the 

 jduvial period, or to aerial denudation, Avhich is almost the only force 

 active since the pluvial period. It is to this force — aerial denuda- 

 tion — that the formation of table mountains is to be attributed. 

 These occur fre(|uently in the central belt of plain land an.d oft^'u stand 

 together in groups. The thickness of the overlying deposits is not 

 very great. So far as I could tell, it i)i'obably nowhere exceeds 100 

 meters. Concerning the chronology of its formation, sufficient })aleon- 

 tologic evidences are still lacking. On my last trip I brought fossils 

 from Schedma — that is, from the extreme southwest — where disturb- 

 ances connected with the upheaval of the Atlas are still important 

 factors. E. Fichcur, who probably possesses the greatest knoAvledge 

 of the geologic construction of Algeria, ascribed these fossils to the 

 Cretaceous period. Going ui)on this assumption, I am of the opinion 

 that the winding valley of the Tensift, which I followed in 1890 almost 

 from its mouth to the sub-Atlantic high plateau at Marrakesh, was 

 cut into this rock. According to A.Brives, state geologist in Algeria, 

 and the first geologist to explore a portion of the Atlas Vorland, in 

 the winter of 1901-2, the overlying mountains between the Tensift 

 and the Um-er-Kbia, and north of this region, are to be ascribed for 

 the most part to the Miocene period. The investigations of this geol- 

 ogist in Morocco are knowm only through a preliminary publication. 

 Accordingly, the Atlas Vorland for the most part has the character 

 of stratified table-land. The dominating feature is that of plains — in 

 fact, high plateaus. As far as our present knowledge goes, it may 

 be assumed that two periods of uplift occurred, the owo in Eocene 

 and the other in Quaternary time. Consecpiently there are two 

 levels — the coast plains and the high inland plateau — which comprise 

 the gi-eatest portion of the Vorland. The coast plain, whose geologic 

 conditions I was able to distinguish clearly in my last trip (1901), 

 begins at Cape Hadid, 20 kilometers north of Mogador, in a narrow 

 point. At the foot of I)j. Achdar, which is the dominating landmark 

 of central Morocco — that is, at Sidi Kehal— where the nnich-traveled 

 caravan route from INIazagan to Marrakesh, in the valley of ]Mtal, 

 climbs up to the higher level, the coast plain reaches its greatest 



