der. They have a skeleton of a dozen or so woody rods that may 

 reach two inches in diameter and are immensely strong, to hold 

 aloft the tons of pithy "flesh" and the thick, solid skin. 



These giant cactuses are all vertically fluted and carry bunches 

 of spines on series of knots running up their ridges. Those of the 

 Saguaro are of two kinds, one black and stiff, borne by young 

 trees for their first half-century, the other yellow and pliable, 

 developed by older specimens. The Organpipe is the common 

 form of lower Sonora and Baja California, though Pringle's is 

 also found there. The Organpipe is formed, as its name implies, 

 of a number of great pipelike stems, looking not unlike a bunch 

 of enormous upright cucumbers from a distance. These are also 

 fluted but more shallowly, and they are usually ringed or 

 pinched at irregular intervals, a characteristic caused by frosts 

 or periods of low temperature which restrict their growth or 

 temporarily kill their growing points. Organpipes have edible 

 red fruits covered with soft spines that can be brushed off. The 

 fruits of many cactuses are edible and some are delicious; that 

 of the Saguaro is very sugary, of the Prickly Pears excellent. The 

 seeds of some can be ground into a fine meal. 



There are about 450 other species of Cerei. Their headquarters 

 are subtropical Central America (that is to say south of the 

 Tropic of Cancer to 10 degrees north); some just reach into the 

 United States. They are numerous in the West Indies, both in the 

 arid areas that cover most of the Greater Antilles and in the wet 

 forests of the Lesser Antilles; (hey are everywhere up to the 

 montane forests of Mexico; and there are many in South 

 America. Among them are the cactuses which are universally 

 most admired for their blooms and which have been given such 

 names as King-of-the-Night, Princess-of-the-Night and Midnight- 

 Ladies. Personally I prefer the name Moonflowers. These are 

 mostly white, tinged with most delicate salmon pinks and golds, 

 and they pop unexpectedly out of dry, ropelike tangles or from 

 pale blue, fleshy, leaflike straps. Some have a very powerful 

 aroma. 



STRANGE FRUITS 



As I said above, the cactuses, although the dominant plants of 

 the true Desert Belt, are not by any means the only ones, for 

 in the places of most appalling aridity there is a considerable 

 variety of other families of plants in addition to the ocotillos, 

 yuccas, and agaves. Some of them look rather like cactuses, 

 notably the Candelilla (canday-lee-ah). This is a member of the 

 euphorbia or spurge family, but is very cactus-like. Members of 

 this family replace the cactuses in African deserts. The Candelilla 

 grows in large masses of asparagus-like stems and is known also 

 as the Wax Plant; its scientific name is Euphorbia anlisyphilitica. 

 It yields a wax which is used in the manufacture of candles, floor 

 and polishing waxes, shoe polish, and phonograph records. In 

 Mexico, as its scientific name implies, it is a recognized item in 

 the treatment of venereal disease. 



The ubiquitous Creosote Bush also can exist almost anywhere 

 that a cactus can. This is a small evergreen shrub with small 

 leaves and tiny, bright yellow flowers. Its leaves are sticky and 

 it smells of creosote. Cattle will not eat it, but a lotion used to be 

 made by soaking its leaves and stems in boiling water; this was 

 considered efficacious in treating cuts and bruises of both man 

 and beast, especially saddle sores on horses. Also in the true 

 desert there is some Saltbush, the little acacia known as the 

 Catsclaw, and occasional stunted Allthorn — an apt name for a 

 thing that is literally, when not in its tiny flower, all thorns. 

 There are herbaceous plants in readiness to spring up as soon 



as it rains, but just about the only one that somehow manages to 

 put in an occasional appearance at other times is a thistle. 



Conditions, of course, are altogether different as soon as one 

 passes from the Desert Belt itself into its enveloping scrub zones. 

 Of the Northern Scrub Belt we have already spoken at length in 

 Chapters 14 to 17, and we shall visit it again in the next chapter. 

 The Southern Scrub Belt will be encountered later in its rather 

 specialized form on the upland plateau of Mexico, and has 

 already been described in a still more particular form, in Chap- 

 ter 14, which dealt with the East Chaparrals. However, there is 

 in the province we are discussing a wide belt of Southern Scrub 

 running down the east side of the desert from the mountains of 

 Arizona to the Gulf of California and then appearing again on 

 the tip of the peninsula of Baja California. This merges with the 

 desert on one side and actually penetrates it to a very large 

 extent. On the other side it merges with the subtropical Savan- 

 nah Belt, which extends northward from the coast of Mexico 

 and thins out against the Sierra Occidental. 



This strip of scrub is significant and rather distinctive. In this, 

 despite no noticeable increase in mean average annual rainfall, 

 conditions are quite different from those of the Desert Belt or the 

 Northern Scrub Belt. The same kinds of plants occur but much 

 more exuberantly, and they are interspersed with a whole host 

 of others, many of a woody nature, such as the giant heather 

 called the Madrone with its coppery smooth bark, as well as 

 mesquites, ironwoods, great groves of yuccas, century plants, 

 agaves, and many herbs. In fact, although the ground itself re- 

 mains a desert and grass is absent but for a few scattered and 

 minute specialized areas, the dry-stalked herbs, scrubby bushes, 

 small trees, and thorny shrubs actually coalesce to form a for- 

 est — and a closed-canopy one at that. If there has been rain of 

 any consequence before the vegetating season in the spring, 

 this heterogenous mass may burst into flower and be exquisitely 

 beautiful, with cicadas whirring and bees buzzing by the mil- 

 lions everywhere. 



Passing from this zone westward to the desert in southern 

 Sonora can be almost as startling as stepping out of a tall equa- 

 torial rain forest onto the Orchardbush Belt; for, although the 

 two zones merge over most of their range, there are places where 

 you can literally have your right foot in the Desert and your left 

 in the Scrub Belt. 



THEY TREAD WARILY 



Introduced domestic animals of the larger varieties tramp about 

 in both the Scrub and Desert Belts and do not seem to be much 

 affected by the spines and thorns of the cactuses and other 

 plants. They do not eat cactuses except during extreme droughts, 

 when some prickly pears are rendered edible by the burning off 

 of spines. The larger indigenous fauna, however, seems to find 

 these spiny things rather irksome and treat them with about the 



Above left: The Gila Monster, a slow-moving, obese form 

 of lizard. It produces a copious poison which flows out of 

 glands and down its guttered teeth. 



Above right: Prominent among the multitudinous rabbits 

 found in these deserts is the little Desert Cottontail. 



Below: The Desert Tortoise seems to be immune to heat 

 and desiccation but actually spends most of its time in the 

 shade or under rocks. 



262 



