SllttftrattfltuJ of pi;gto-<tosrajpf}g. 



XIX 



; Cactus vegetation, affording shelter 



I against the sun to the young plants, a 

 I < couple of Agaves also typical of Mexico, 



and some herbs, are distributed over the 



I I soil, as yet the roving-grouud of the wild 

 i i Indian. Young plants of Cereus giganteus 

 '■ i retain a globular shape for several years ; 

 i I and thev begin to flower when about ten 

 1 1 to twelve feet high. We have actual mea- 

 1 j sureinent of stems 46 feet high, so that 



1 there is nothing improbable in Colonel 

 Emory's disputed statement that the Cereus 

 attains 50 to 60 feet in height. The stem 

 is thickest at or a little above the middle, 

 and tapers upwards and downwards. It is 

 mostly simple, but the older ones hare 

 often a few erect branches. Both stem and 

 branches are ribbed, almost fluted like co- 

 lumns, and covered with bundles of spines. 

 The flowers are produced in abundance 

 near the summit, and the fruit has a crim- 

 son-coloured, sweet, but rather insipid 

 pulp. [B.S.] 



HYPH^XE OR DOUM PALM-TREES 

 IN UPPER EGYPT. 



(Plate XVIII.) 



As the traveller is leaving the lower and 

 gradually ascending into the upper por- 

 tion of Egypt, he meets with the most 

 characteristic of African trees, in the 

 shape of branched Palms, the famous 

 Hyphcene thebaica. They are seen in their 

 full beauty about the cataracts of the Nile, 

 as represented in our plate. The contrast 

 between these trees and the rest of the 

 palm tribe i3 very great. "Whilst most of 

 the palms have a straight pole to which at 

 the upper extremity a number of feathery 

 , leaves are attached, we have here a regu- 

 i larly branched tree, somewhat like a screw- 

 ■ pine or Pandanus, and large fan-shaped 

 ! leaves, between which grow large bunches 

 I of light yellow fruits with a thick mealy 

 ! rind, so much resembling in look and 

 j taste real gingerbread as to have conferred 

 I upon the palm the name of Gingerbread 

 j tree. In Cairo and other towns of Egypt 

 | these bunches are exposed for sale in the 

 I market-places, together with dates, figs, 

 i oranges, and other produce of the country. 

 The wood of the tree is used for various 

 , domestic purposes; the seed of the fruit is 

 : eaten ; and the kernels turned into beads 

 | for rosaries, and at Kano into toys. From 

 ! the hieroglyphics we know that it was cul- 

 I tivated more than 4,000 years ago in and 

 | about Thebes ; but though always a leading 

 I tree and a most striking object of the 

 Egyptian landscape of the Upper Nile, the 

 Hyphcene dova not seem to have exercised, 

 as far as we know, any decisive influence 

 upon ancient Egyptian architecture, like 

 the date palm (Phcenix dactylifera) and the 

 j Deleb palm (Borassusl cethiopum), for in- 

 i stance, have done. The peculiar swelling 



of ancient columns is evidently copied 

 from the trunk of the Deleb palm, of "which 

 a singular bulging out is oue of the most 

 striking characteristics ; whilst the capi- 

 tals of the column are, in many instances, 

 slavish copies of the crowns of the date- 

 palm, as may be seen in the ancient temple 

 at Edfoo. The exact geographical range 

 of Hyphcene thebaica has as yet to be ascer- 

 tained. We know it extends considerably 

 into Central Af rica,but do not know exactly 

 where it leaves off, as we have no botanical 

 specimens to decide the question, and have 

 to depend upon the information of travel- j 

 lers not able to discriminate between this i 

 species and those allied to it. It is certain, 

 however, that there are more than one I 

 species of Hyphcene, and that some, of 

 them at least have a straight cylindrical 

 and unbranched trunk, like that of the 

 generality of palms. [B. S.J 



VEGETATION ON THE ICE-CLIFFS IN 

 KOTZEBUE SOUND, ARCTIC AMERICA. 



(Plate XIX.) 



The soil of the Arctic region is always 

 frozen, and merely thaws during the sum- 

 mer months a few feet below the surface. 

 But the thawing is by no means uniform. 

 In peat it extends not deeper than two 

 feet, while in other formations, especially 

 in sand or gravel, the ground is free from 

 frost to the depth of nearly a fathom. The 

 roots of the plants, even those of shrubs 

 and trees, do not penetrate into the frozen 

 subsoil. On reaching it they recoil as if 

 they touched upon a rock through which 

 no passage could be forced. It may be sur- 

 prising to behold a vegetation flourishing 

 under such circumstances, existing inde- 

 pendent as it were of terrestrial heat. But 

 surprise is changed into amazement on 

 visiting Ko.tzebue Sound, where, on the 

 top of icebergs, herbs and shrubs are 

 thriving with a luxuriance only equalled in 

 more favoured climes. There, from Ele- 

 phant to Eschscholtz Point, is a series of 

 cliffs from 70 to 90 feet high, whicM present 

 some striking illustrations of the manner 

 in which Arctic plants grow. As may be 

 seen in our plate, three distinct layers 

 compose these cliffs. The lower, as far as 

 it can be seen above the ground, is ice, 

 pure ice, and from 20 to 50 feet high. The 

 central is clay, varying in thickness from 

 2 to 20 feet, and being intermingled with 

 remains of fossil elephants, horses, deer, 

 and musk oxen. The clay is covered with 

 peat, the third layer, bearing the vegeta- 

 tion to which it owes its existence. Every 

 year, during July, August, and September, 

 masses of the ice melt, by which the up- 

 permost layers are deprived of support and 

 tumble down. A complete chaos is thus 

 created; ice, plants, bones, peat, clay, are 

 mixed in the most disorderly manner. It 



