These dissimilarities are but a few of the surprises which abound in this singular family, and which render it extremely attractive to the student of nature's wondrous and never-ceasing diversity and beauty.

The cactuses are peculiarly American plants. There is but one of the thousand described species which is indigenous to other countries, and that one is so unlike ordinary cacti that one would scarcely think of associating it with them. This plant is a rhipsalis, closely allied to the mistletoe cactus of greenhouses. The home of the cactus family is in the deserts of the southwestern United States and Mexico and the Andean region of South America. They appear to have been developed through long ages to suit the peculiar climates of those regions. In other desert regions there are plants which are similar in form and yet very different in botanical character. This is particularly true of the great desert region of southern Africa, which is inhabited by many plants so nearly like the cactuses as to be mistaken for them by the ordinary observer, but which belong to an entirely different division of the vegetable kingdom. These cactus-form plants are euphorbias, many species of which inhabit this country, but which attain a fleshy character only in desert regions. The euphorbias are to southern Africa much what the cacti are to Arizona and Mexico. Fig. K represents one of these cactus-form plants, and one which is often seen in houses, Euphorbia meloformis, or melon-like euphorbia.

Even the common Euphorbia splendens, grown everywhere, is often mistaken for a cactus. But this confusion of fleshy and spiny plants with cactuses is general. Aloes, agaves, house-leeks and yuccas are often mistaken for them. And in fact some of these very plants dispute with cactuses the possession of the deserts. In our southwestern regions the yuccas rise to tree-like stature, with thickened and hardened stems, and many other plants, notably the agaves, take on somewhat similar characters. All this only illustrates the type of vegetation which desert regions demand. Characteristic American desert landscapes are shown in Figs. A (p. 451), P(p. 468) and PP(p. 469).

It will be necessary to go somewhat into detail in the geographical distribution of these and a few similar plants, in order to understand more perfectly their relationships and characteristics. All this bears directly upon cultivation, for it not only enables us to understand their requirements better, but it affords us an inexhaustible source of pleasure as a mere matter of knowledge. Our interest in cultivating plants is due quite as much to a general knowledge of their habits and characteristics as to the beauty of their forms or flowers.

In the northeastern United States there are very few cactuses. There are only four which grow wild east of the Mississippi and north of Virginia, and these all belong to the Indian fig genus or opun-t i a. Opuntia Rafinesquii (Fig. I) extends farthest north. It is not infre-quent upon sandy plains in Michigan, Wis-con sin and Minnesota, and it extends southward to Florida, and it reaches northward along the coast to Massachusetts. It is a neat and attractive species, well worth cultivating. In Dakota there are two wild species of another genus, mamillaria. Upon the distribution of cacti in the United States, the late Dr. Engelmann wrote, in 1856, as follows :

"As to the geographical distribution of the cactaceae, our territory may properly be divided into eight regions, namely :

"1. The Atlantic Region, which has only a single opuntia, and that peculiar to it. Along the southern coast some West Indian species may yet be expected.

"2. The Mississippi Region, including the Western States, produces another opuntia, which, in different distinct forms, extends into the third, fourth and fifth regions.

"3. The Missouri Region, namely, the northwestern or upper Missouri territory to the Rocky mountains. It furnishes two mamillarias, both extending into the fourth and fifth regions; and three opuntias, one of which only is peculiar to it.

"4. The Texan Region, namely, the eastern and inhabited parts of Texas, westward to the San Pedro, and northward including the territory south of the Arkansas river. This region produces five mamillarias, two of them peculiar to this district; three ecbinocacti, none of which are found in any other of our regions; six cerei, all of them peculiar to this district, and six opuntias, of which only three are restricted to it, and among them is only a single cylindric opuntia. This region contains therefore altogether twenty species, fourteen of which are peculiar to it.

"5. The New Mexican Region, namely, western, uninhabited mountainous Texas, and eastern New Mexico to the eastern headwaters of the Colorado of California. This region is our richest cactus district. It has furnished sixty-five species, fifty-five of which are peculiar to it, namely : nineteen mamillarias, of which sixteen are peculiar ; nine echinocacti, all of them belonging to this district only ; sixteen cerei, fourteen of which are peculiar, and one common also to other regions ; and twentytwo opuntias; of these last twelve are flat jointed, four clavate, and five cylindrical ones; seventeen of these species are peculiar.

"6. The Gila Region, comprising the whole valley of the Colorado south of latitude 360 and the country of the Gila, its large southern tributary. This has thus far furnished thirty-six cactaceae, namely, five marail-larias, three of them peculiar species; six echinocacti, none of them found elsewhere; seven cerei. representatives of each of our four sub-genera, and five of them peculiar ; eighteen opuntias, of which six (all peculiar) belong to the flat kinds, two to the clavate and ten to the cylindric division; one of the former and nine of the latter are peculiar.

"7. The California Region, namely, California west of the Sierra Nevada, and comprising the southwestern part of the present state of California, produces six cactaceae, five of which are peculiar. They are one mamillaria, one echinocactus, one cereus and three opuntias.