APPENDIX H.

Notes on the Geology of the Plain of Marocco and the Great Atlas.

By George Maw, F.G.S., F.L.S., &c.

Of the Geology of Barbary little information has hitherto been put on record. The only publications with which I am acquainted are some notes on the geological features of the district between Tangier and Marocco in Lieut. Washington’s ‘Geographical Notice of the Empire of Marocco,’ published in the first volume of the ‘Journal of the Royal Geographical Society;’ a few cursory remarks on the Marocco Plain by Dr. Hodgkin, in his account of Sir Moses Montefiore’s ‘Mission to Morocco in 1864;’ a short paper, by Mr. G. B. Stacey, on the subsidence of the coast near Benghazi, published in the twenty-third volume of the ‘Quarterly Journal of the Geological Society;’ a report by M. Mourlon on some rocks and fossils in the Museum of Brussels, collected in the north-west of Marocco by M. Desquin, a Belgian engineer, published in Vol. XXX. of the ‘Bulletin de l’Académie Royale de Belgique,’ for 1870, to which I shall have further occasion to refer; a geological memoir, by M. Coquand (‘Bull. de la Soc. Géolog. de France,’ vol. iv. p. 1188), on the environs of Tangier and northern part of Marocco; and finally, a paper I read before the Geological Society of London in 1872.

Barbary, with the exception of the immediate neighbourhood of a few of the ports, has been almost inaccessible to Europeans; and the extreme jealousy of the Moorish Government with reference to the mineral riches of the country has hitherto prevented any geological investigation. In the year 1869 I visited the northern portion of Marocco, including the Tangier and Tetuan promontory, and during the spring of 1871 accompanied Dr. Hooker and Mr. Ball to Mogador, the city of Marocco and the Great Atlas, permission for our visit having been obtained from the late Sultan through representations made to the Moorish Government by Lord Granville through Sir John D. Hay, our Minister Plenipotentiary at Tangier.

The object of the second journey was mainly botanical; and as an engagement was given by Dr. Hooker that we should not collect minerals, the opportunities for geological investigation were very limited.

The observations I was able to make on the structure of the great chain, which had not been previously ascended by a European, and of the plain of Marocco, are embodied in the accompanying section. Stopping for about a fortnight at Tangier, we made several excursions in the neighbourhood. The western part of the northern promontory of Marocco, facing the Straits of Gibraltar, consists of highly-contorted beds of hard courses interstratified with brindled yellowish sandstones and variegated puce and grey marls, having a general dip to the south-east, but so twisted about that the dip and strike are often reversed within a few feet. The country has a general undulating contour, here and there rising up into ridges of from 2,000 to 3,000 feet, in which the hard bands weathered out from the softer strata are strikingly prominent from a great distance.

We observed no palæontological evidence of their age; but, judging from their resemblance to the cliff-sections near Saffi, where fossils occur, they are presumably Neocomian or Cretaceous.

Fucoids were collected by M. Coquand in the vicinity of Tangier, in beds considered by him to be representatives of the Upper Chalk; but M. Mourlon, referring to the works of Pareto and Studer on the nummulitic rocks of the Northern Apennines and Switzerland, inclines to place the Tangier fucoid beds above the nummulitic horizon, and as part of the Upper Eocene. But near the villages of Souani and Meharain, a little to the south of Tangier, undoubted Cretaceous fossils were met with by M. Desquin, including