74 



THE POPULAR SCIENCE MONTHLY. 



sugar or honey. These ants apparently prefer 

 elevated situations, but doubt is thrown over 

 this by their having been mentioned as seen 

 at Matamoras, which is but little above the 

 level of the sea. Their nests are built on 

 the tops of the ridges, and are marked ex- 

 ternally by small moundlets of gravel six or 

 seven inches in diameter, and two or three 

 inches high ; internally they present ramifi- 

 cations of galleries and enlarged chambers 

 in several stories, within which the honey- 

 bearers exist, clinging to the roof of the 

 vault. The honey is gathered by another 

 class of workers from the galls of a species 

 of oak, where Dr. McCook found it in the 

 shape of globules which had been exuded 

 from the gall, and is conveyed to the honey- 

 bearers by regurgitation. It is " very pleas- 

 ant, with a peculiar aromatic flavor, sug- 

 gestive of bee-honey, and quite agreeable." 

 Dr. Loew also describes it as having an 

 agreeable 'taste, slightly acid in summer 

 from a trace of formic acid, but perfectly 

 neutral in autumn and winter. The sirup 

 extracted from the ants had an odor like 

 that of the sirup of squills, and dried, when 

 heated, into a gummy mass, which quickly 

 became soft by the absorption of water from 

 the atmosphere, and the alcoholic solution of 

 which had the smell of perfumed bay-rum. 

 The honey is gathered by the Mexicans and 

 Indians, is eaten freely and regarded as a 

 dainty morsel, and is fermented into an 

 alcoholic product. It can never be got in 

 large enough quantities to make it of eco- 

 nomical value, even if that were desirable. 

 The ants, showing the same traits as all 

 other species that have been observed, take 

 most excellent routine care of the honey- 

 bearers and of the larva?, but seem wholly 

 indifferent to occasions calling for care or 

 sympathy which happen to be out of the 

 regular line. Their chambers are construct- 

 ed with the architectural skill that is shown 

 by their making the floors perfectly smooth, 

 so that their progress and work shall be 

 facilitated as much as possible, and by their 

 making or leaving the roofs rough, so that 

 the honey-bearers may cling more securely 

 to them. The Occident ant is the most 

 numerous species of animal on the Western 

 Plains, and, after the prairie-dog, affords 

 the most prominent marks of its presence 

 everywhere on their surface; yet Dr. Mc- 



Cook's memoir, forming the second half of 

 this volume, is the first that has been pub- 

 lished about them. Their habits are similar 

 to those of the harvesting ant of Florida, 

 the agricultural ant of Texas, and some 

 harvesting ants that have been observed in 

 Pennsylvania and New Jersey. They have 

 been found from Brookville, Kansas, to 

 Keno, Nevada, through twenty-one degrees 

 of longitude, and range probably from 32 

 to 45 north latitude. They build their nests, 

 which are marked by elliptical cones some- 

 times ten inches or a foot high, in slopes 

 and flats, avoiding the ridges. The mounds 

 are surrounded by cleared spaces which are 

 sometimes ten feet or more in diameter, and 

 appear to have been purposely stripped of 

 vegetation, while the surrounding grass is 

 penetrated by paths leading out. All of the 

 mounds are covered with pebbles of the 

 nature of the gravelly soil in which they 

 stand, which appear to be collected by the 

 ants and brought to the spot, if necessary. 

 One of the insects was observed to carry a 

 stone of six times its weight over a space of 

 three hundred times its length and up in- 

 clines. These ants are evidently harvesters, 

 gathering seeds and storing them in their 

 nests, which are chambered under-ground, 

 sometimes to a depth of eight or nine feet, 

 and are not essentially different in their in- 

 terior construction from those of the honey- 

 ant. Dr. McCook observed them gathering 

 seeds of the sunflower, of a euphorbia, of 

 an amaranthus, of the gramma-grass of the 

 country, and of other plants. Their nests 

 are infested by six or seven species of para- 

 sitic ants, toward which they show no liking, 

 but no particular hostility, of two of which, 

 the erratic ants and the fetid ants, an in- 

 teresting account is given. Dr. McCook 

 confines himself to relating and illustrating 

 the facts he has observed, leaving inferences 

 to be drawn by others ; and he has made a 

 valuable addition to the literature of a sub- 

 ject that engages the attention of the most 

 distinguished naturalists. 



Suicide : Studies on its Philosophy, Causes, 

 and Prevention. By James J. O'Dea, 

 M. D. New York : G. P. Putnam's Sons. 

 1882. Pp. 322. Price, $1.16. 



The author defines suicide as the inten- 

 tional destruction of one's own life, and ex- 

 cludes from the category deaths from acts 



