Nevada County picayune., 1889-08-14
ABOUT ANTS COWS
yacts Concerning Plant Lice ana tho iA
 sects That Feed on Them.

sects That Feed on Them.
 Have you ever noticed some of tho leaves on youQ rose-bush curled ol rolled up in aR odd manner, as | shrinking from the sunlight?
 Noticing this, did you ever endeavoi to satisfy your curiosity by investlgat ing the cause of this apparent ditfi' dence. If you had taken the trouble to unroll one of these leaves you woulo have found number of minute insects sheltered by it's encircling folds. SC small indeed, are these insects that nc adequate idea of their shape can be asccrtained except by resOrting to your microscope, Unde.' the glass these llt- tie individuals assume definite propor' tions. and their bodies are found to be hask-shaped, with two little tubes pro. jecting from the posterior portion oi the abdomen.
 Now, these two little tubes are oi great importance, and insure careful treatment to many an aphis Gas these little plant lice are calleD, for from these tubes cxudes sweet fluid SC. creted by the stomach, which Is highly prized by ants, and to secure which the ants tenderly watch over and care for the little aphides. They carry them out in the morning and place them on the leaves of some juicy plant, and then In the evening they bring them back to their own nests. In return for this kindness the aphides, when caressed by the antenn8, or 'feelers," of the ant emits this sweet fluid, which is gre4dily devoured by that industrious insect This fact has caused the plant lice to be frequently spoken of as "snt's cows" They gain their live libood from the juices of plants, which they suck up, and it is this depriving the leaf of part of its sap that causes it to curl up, thus protect ing it's enemy and returning good for evil, But the aphis is not without it's enemies, for the little "lady bugs" ask for no daintier morsel than nice, juicy plant louse. Besides these, the larva of a species of lace-winged fly has such fondness for diet of plant lice that it has received the appellation of the aphis lion.
 In Europe gardeners frequently take the pains of hunting up number oi these aphis lions, which they place on their infested bushes, and as a result the plants are soon freed from plant lice. Now, the plant-louse differs from nearly all other insects in one respect. It does not lay an egg from which are matched little grubs that finally develop into mature in- sects, but instead the females in the fall lay eggs which remain over winter and early in the spring hatch out, when it is found that, without eXcep- tion, all are females. Now comes the curious part, for these individuals bring forth living young, which, too, are only females, and are winglcss. Generation number two follows the eX- ample of its predecessor and so on un. til the approach of autumn, when a brood of perfect males and females is brought forth. The females of this brood lay eggs which remain over win ter and undergo the same process as before.
 NJ. Fougard says that the ordinary aphiS produces ten generations during year, and that each insect also brings forth about ten young ones, as seen in the following table:
 1st generation, aphis; 2d genera tion, 100 aphides; Sd, 10000; ith, L. GOO, GOO; 9th, 1OO,OO0,0OO; 9th. 10000 GOO, ,0O0 Eth, 1000, 00o 100000; Sth, 100, 900, GOO, 100000; 9th, 10000, ,0O0. GOO, GOO, 600; 10th, 1000, ,000, 900, ,000,- GOO, GOO.
 So that from this one aphis in the spring would come one quiutillion in the fall, were it not for its many ene- mics. A striking example of this enormous increase is the following from Prof. Huxley: Il will assume that an aphis weighs one one-thou- sandth of a grain. which is under the mark; quintillion will, on this esti- mate, weigh quadrillion of grains. He is very stout man who weighs two million grains, consequently, the tenth brood alone, if all its members survive the perils to which they are exposed. contains more substance than five hundred million stout men; to say the least, more than the whole popula- ton of China. Noble M. Ebcrhart, Ph D., in Chicago Journal.