General Physical and 7\>pi)t/rnp/ttcal Featitres. 15 



western porti(jn of the interior of the culuny, and stretches southward 

 from the Cuyuni River to within 30 miles above the mouth of the 

 Ireng River, and eastwards to the Essequib > River between the 

 Potaro and Rupununi Rivers, whilst certain s^jurs of these mountains 

 continue beyond the Essequibo River right across the colony as far as 

 the Courantyne River. 



The bulk of these mountains form a successive series of terraces and 

 broad, undulating plateaus, with bold, and in some cases, perpendicular 

 sandstone escarpments varying in Jieight from about 1,200 feet to over 

 2,000 feet, and eventually forming a large undulating tableland at an 

 average height of about 3,500 feet above the sea level. In many parts 

 of the mountains and tablelands great and deep gorges have been 

 eroded liy the rivers and streams which traveise them. They attain 

 their greatest height at Mount Roraima and Mount Kukenaam, both 

 of which rise over 8,500 feet above the sea. The portion of this range, 

 which extends westward and down the southern bank of the Mazaruni 

 River to the vicinity of the Teboco Cataracts, retains the striking 

 tiat-topped features, and is known as the Merume Mountains. 



The elevated tableland (8,635 feet) of Mount Roraima is about 

 twelve square miles in area, and on it the bouHdaries of the colony, 

 with those of Venezuela and Brazil, meet at a common point. This 

 very remarkable mountain, together with Mount Kukenaam, is 

 a part of one of the most extensive sandstone formations on the globe, 

 and they both rise with perpendicular clifi's of sandstone 2,000 feet in 

 height above the base of the surrounding country. Although Mount 

 Roraima has, to some extent, been explored by several parties, 

 amongst whom may be mentioned Sir Everard im Thurn, and 

 Mr. H. I. Perkins, I.S.O., Messrs. Quelch and McConnell, and the 

 Venezuelan Boundary Commissioners, theie still remain many unsolved 

 problems to attract the attention of the explorer, and many further 

 discoveries, more especially for the botanist, on this and the other 

 somewhat similar remarkable mountains of this range. 



Of these other sandstone mountains, the highest (about 7,000 feet 

 aliove the sea) and most conspicuous are the curiously shaped ones of 

 Iwalkarima, Eluwarima, Ilutipu, and Waiaka-piapu, the last-mentioned 

 resembling an obelisk with a truncated head. None of these have as 

 yet been explored. Many extraordinarily high waterfalls descend 

 over the perpendicular cliffs of most of these mountains, those at 

 Roraima and at Kukenaam having sheer drops of nearly 2,000 feet. 



The Pakaiaima Mountains are partly covered with forest, more 

 especially in the valleys, but the greater portion of the elevated 

 l)lateaus formed by this range are grass-clad, as are also the mountain- 

 heights towards the south. In the valleys, and on certain of the 

 slopes, high forests are found ; but on the higher elevated plateaus the 

 forest becomes very stunted and forms very dense and impenetrable 

 thickets. The highest plateaus, such as Mount Roraima, are mostly 

 bare, exposed expanses of rock, between the crevices of which grow 

 many rare and curious orchids and other flowering plants, besides some 

 low bushes and extremely stunted trees. 



