86o 



POPULAR SCIENCE MONTHLY. 



answers, eight hundred and ninety-seven of 

 which came from the United States and the 

 rest from the Canadian provinces. These 

 reports showed that in many localities, par- 

 ticularly in the East and South, but little at- 

 tention is paid to keeping varieties pure, and 

 many farmers use mixed, unknown, or local 

 varieties of ordinary merit for seed. In 

 New England but little grain is grown from 

 sowing, owing to the cheapness of Western 

 grain, and wheat is rarely reported. Oats 

 are now mostly sown from Western seed, and 

 the resulting crop is mown for hay, while 

 most of the corn is cut for green fodder or 

 silage. On certain fine lowlands — as, for ex- 

 ample, in the Connecticut Valley — oats, and 

 more especially corn, are often grown for 

 grain. While reports on most of the cereals 

 were rendered from the lower austral zone, 

 or the region south of the Appalachians and 

 the old Missouri Compromise line, this region, 

 except where it merges with the upper aus- 

 tral or the one north of it, is apparently out- 

 side the area of profitable cultivation of 

 wheat and oats. In Louisiana and most of 

 the other parts of the lower austral, except 

 in northern Texas and Oklahoma, wheat is 

 almost an unknown crop. The warm, moist 

 climatic conditions here favor the develop- 

 ment of fungous diseases to such a degree 

 that the plants are usually ruined or greatly 

 injured at an early stage of growth. In 

 Florida, as a rule, cereals are rarely culti- 

 vated except on the uplands at the northern 

 end of the State. In a general way, corn 

 and wheat are most successfully grown in 

 the upper austral zone, or central States, 

 while oats are best and most productive in 

 the transition zone (or northern and Lake 

 States and the Dakotas), or along the border 

 of the upper austral and transition. The 

 gradual acclimation of varieties of cereals, 

 through years of selection and cultivation, 

 has gone so far, however, that some varieties 

 are now much better adapted to one zone 

 than to another. 



Spanish Silkworm Got. — The business 

 of manufacturing silkworm gut in Spain is 

 a considerable industry. The method of 

 preparation is thus described in the Journal 

 of the Society of Arts : After the silkworm 

 grub has eaten enough mulberry leaves, and 

 before it begins to spin, which is during the 



months of May and June, it is thrown into 

 vinegar for several hours. The insect is 

 killed and the substance which the grub, if 

 alive, would have spun into a cocoon is 

 drawn out from the dead worm into a much 

 thicker and shorter silken thread, in which 

 operation considerable dexterity and experi- 

 ence are required. Two thick threads from 

 each grub are placed for about four hours in 

 clear cold water, after which they are put 

 for ten or fifteen minutes in a solution of 

 some caustic. This loosens a fine outer 

 skin on the threads, which is removed by 

 the hands, the workman holding the threads 

 in his teeth. The silk is then hung up to 

 dry in a shady place, the sun rendering it 

 brittle. In some parts of the country these 

 silk guts are bleached with sulphur vapor, 

 which makes them beautifully glossy and 

 snow-white, while those naturally dried have 

 a yellowish tint. The quality of the gut is 

 decided according to the healthy condition of 

 the worm, round indicating a good quality 

 and flat an inferior one. 



The Nests of Burrowing Bees. — Prof. 



John B. Smith, having explained to his sec- 

 tion of the American Association a method 

 which has been successfully applied, of tak- 

 ing casts in plaster of Paris of the homes of 

 burrowing insects, with their branchings, to 

 the depth of six feet, described some of the 

 results of its application. Bees, of the genus 

 Calletes, dig vertically to the depth of eight- 

 een inches or more, then burrow horizon- 

 tally from two to five inches farther, and 

 construct a thin, parchmentlike cell of sa- 

 liva, in which the egg is deposited, with pol- 

 len and honey for the food of the larva. 

 They then start a new horizontal burrow a 

 little distance from the first, and perhaps a 

 third, but no more. The vertical tubes are 

 then filled up, so that when the bees come 

 to life they must burrow from six to twenty- 

 four inches before they can reach the sur- 

 face. Another genus makes a twisted bur- 

 row ; another makes a vertical burrow that 

 may be six feet deep. About a foot below 

 the surface it sends off a lateral branch, 

 and in this it excavates a chamber from 

 one to two and a half inches in diameter. 

 Tubes are sent down from this chamber, as 

 many perhaps as from six to twenty togeth- 

 er, and these are lined with clay to make 



