THE CACTUS FAMILY. 



473 



The flattened tubercules have been supposed to bear 

 . some resemblance to a hatchet, and, instead of spines 

 at the apex, they are furnished, with two rows of hard 

 scales, which appear like those on the back of a wood- 



FiG. Q. Cereus chloranthus. 



louse ; and these suggested the specific name. The 

 flowers, borne at the apex of the plant, are large and of 

 a showy purple color. There are several varieties, and 

 all are natives of Mexico. 



The leuchtenbergia, as in the preceding genus, has 

 but a single representative, L. principis (Fig, O). If we 

 except the flowers, it bears very little resemblance to 

 any other form of cactus, being, in fact, more like an 

 , aloe. The erect, cylindrical, and woody stem is sur- 

 mounted by triangular tubercules, about six inches in 

 length, which bear tufts of dry, rough vegetable fibre at 

 -their extremities. The stem varies in height from one 

 to twelve inches, the lower part of the old plant being 

 clothed with the scale-like remains of former tuber- 

 cules. The large yellow flowers are borne from the 

 axils of the younger tubercules. It is a native of 

 Mexico. 



About two hundred species of echinocactus (See 

 Figs. D, G, H), or hedgehog cactus, have been found 

 in Mexico and various parts of South America. The 

 globular, cylindrical, or oblong stems of thfese plants 

 range in height from a few inches to nine feet. They 



are ridged. The ridges, which are furnished with large 

 and small spines, take a vertical or spiral course, being 

 sometimes divided, so as to form more or less distinct 

 tubercules. The large showy flowers, with red, yellow, 

 purple and white as prevailing colors, open several days 

 in succession during bright weather. 



The genera malacocarpus, gymnocalycium and astro- 

 phytum, still referred to in trade lists, are now placed 

 under echinocactus. E . iiiyriostigiiia is one ot the most 

 singular plants. The stem attains a height of six or 

 eight inches and is regularly divided into either five or 

 six triangular ridges, upon the apex of which, at the 

 summit of the plant, the pretty yellow flowers are freely 

 borne. Spines are conspicuous by their absence, 

 cushion-like tufts of short brownish hairs, regularly 

 disposed along the apex of the ridges, appearing in 

 their stead. The numerous small white spots which 

 mark -the surface have a very pleasing effect against 

 the dark green epidermis. It is a native of Mexico, and 

 commonly called the bishop's hood cactus ; but the 

 solidity of the plant, and its mathematical accuracy 

 of form are more suggestive of the exact proportions of 

 a well-executed metal casting than the work of a hatter. 



The discocactus is a small genus of two or three 

 species, which bear some resemblance to small echino- 

 cacti. They are found in Brazil and the West Indies. 

 The stems, bearing blunt spiny ridges, are about two 

 inches high, and have the form of a flattened globe. 

 The flowers emerge from a woolly mass at the top, and 

 those of D. iiisignis have a very pleasant odor. Disco- 

 cactus should 

 not be c o n - 

 founded with 

 the old genus 

 disocactus, 

 which is now 

 referred to 

 phyllocactus. 



The species 

 of cereus, over 

 200 in number 

 (see Figs. Q, 

 S), have a very 

 extensive dis- 

 tribution, be- 

 ing found i n 

 temperate and 

 tropical Amer- 

 ica, the West 

 Indies, and 

 Galapagos Is- 

 lands. .They 

 are of erect or 

 scandent habit, 

 their stems, 



which vary in height from a few inches to 60 feet, being 

 columnar, globose or triangular. Tufts of spines gen- 

 erally appear on the ridges of the cylindrical types, 

 and also on the edges of the angular ones. The flowers 



Fig. T. Opunti.^ Tuna. 



