POPLAR. 243 POPOCATEPETL. unoqually quadrangular. ])crfcctly smooth leaves. It lias beoonie introduced and well es- tablished in the valleys of the Hudson and Dela- ware rivers and elsewhere. The wood is used for the same purposes as that of the white and gray poplars. The cotton from the seeds has l)een used in Franoc and Germany for making cloth hats and pajier. liut these u.-^es of it were not found profitable. The Lonibardy poplar {Popultis niyra, var. Italica, sometimes called Populus fastigiata and Populus dilitata) is a variety of the black poplar, with erect instead of spreading branches, which appears to have been introduced into Europe from the East, is very common in the Punjab and in Persia, and now also in Lonibardy and other parts of Italy. It attains a height of 100 or even 1.50 feet, and is remarkable for its erect form, contracted head. and very rapid growth. It is sometimes planted as an ornamental tree. Owing to extensive plant- ing during the latter part of the eighteenth cen- tury and the early years of the nineteenth, the tree is a very common one in Europe and America. The balsam poplar or tacaniahac {Populus Ixilsutn- ifcra) , a common ornamental tree, is a native of both Xorth America and Siberia, has viscid leaf- buds and whitish, ovate-oblong leaves, which in spring are of a delicate yellow tint, and have an agreeable fragrance. The erect fastigiate manner of growth approaches that of the Lombard}' pop- lar. The Cottonwood {Populus deltoitles or mon- ilifcru), frequently planted for ornament, is the largest of the jioplars, specimens 150 feet high and 7 feet in diameter being not uncommon in moist soil along rivers and lakes. It abounds from Quebec to the Northwest Territory, and south to Florida and New Jlexico. In Europe it is also known as the black Italian poplar and Canadian poplar. In the Western States the tree is planted for fuel and for its timber, which is considered valuable. Populus hctcrophylla, the swamp poplar, is common from New York to Georgia and west to Arkansas and Texas. It is a tree 80 feet high and has very large cordate leaves. There are a number of other American species, which differ mostly in size of tree and shape of the leaves. Fossil poplar leaves are known in the Cretaceous rocks of (ireenland, and are common in most plant-bearing beds of the Tertiary, differing little from the modern species. POPLAR BLtTFF. A city and the county- seat of Butler County, Mo., 73 miles west by south of Cairo. Illinois: on the Pilack River, and on the Saint Louis. Iron ^fountain and South- ern Railroad (Map: Missouri, F .5). It is situated in a district interested chiefly in lumber- ing and cattle-raising, and carries on a con- siderable trade in its principal manufactures — • lumber and foundry products and brick. The water-works are owned bv the municipality. Popvdation. in 1890, 2187; in 1900, 4321. POPLAR INSECTS. Of several borers which damage the trunks and twigs of both native and Lonibardy poplars. Saiicrda ailrarata is most prominent. The beetles are found and lay their eggs commonly in August and September. The same species also effects Cottonwood in the West- em States. The poplar girdler (.S'aperrfa concolor) frequently girdles the upper liranches of large trees, the beetles issuing about the end of May. BIIOAD-NECKED PRIOSU8 {PrioDIJS luticolJisj. One of the largest of the longicorn beetles of the United States {Prionus lalicollis) lives in the larval state in the trunks and roots of the Loni- bardy poplar, Init also occurs in apple, grapevine, and pine. The poplar goat-moth {Cossus ccnie- rcnsis) lays its eggs commonly upon the bark of the aspen {Pop- ulus trcnniloidcs) and also upon the bark of halm of Gilead {Populus ialsd m ifcru ) . An- other common borer in this tree is the Lomba rdy poplar borer { A g r i I u s (p'auulalus) , and still another is the poplar segeria {.■Egeria tricincta) . A number of cater- pillars attack the leaves, including the common tus- sock-moth caterpil- lar, the poplar span- worm ( larva of Biston iirsayia) , the larva of the Antiopa butterfly, and the larva of the common butterfly Limenitis disippus, as well as the larva of the lo moth and several other moths. The insect fauna of the pojdar in the United States comprises more than 100 species, including several geometrid and noctuid larvte, a number of leaf-miners and leaf-foldors. and sev- eral species of plant-lice. Consult Packard, In- sects hijurious to Forest Trees (Department of Agriculture, Wa.shington, 1890). POPLIN (Fr. popeline, papeline, from It. pn- pnliiKi, poplin, from pupa, pope: so-called because first made at Avignon, the Pajial residence from 1309 to 137fi). In the fifteenth century a fabric was woven in Avignon called pupeline. which was made of silk, and was much esteemed. An at- tempt to imitate it was made in England, and in 1775 the manufacture was introduced to Ireland by French Protestant refugees, and from that time Irish poplins have been famous. What the exact nature of the original pupeliues was is not certainly known ; but the best modern pop- lins consist of a warp of silk and a filling of worsted, which gives substance, combined with great softness and elasticity, to the material. The filling or weft is made heavier than the warp. This gives the material a corded surface re- sembling rep. In double poplin both the w'arp and woof are very heavy, making the corded ap- pearance more prominent. POPOCATEPETL, p6-po'ka-ta-pet'l (Aztec, smoking m<iiiiitain ) . A volcano situated aliout 40 miles southeast of the City of Mexico ( Map : Jlcxico. KB). It rises in the form of a cone to a height of 17.520 feet above sea-level, and is composed chiefly of porphyritic obsidian. For- ests girdle its lower parts, and vegetation ceases only near the snow line. About the period of the Spanish conquest it was very active, but no considerable eruption has been recorded since 1548. though minor eruptions occurred as late as 1802. and the crater still emits fumes. Its crater, which has a diameter of about 2700 feet.
