1644 SEEDAGE 



even temperature is desired, as in bacteriological work. 

 Fresh air or different gases can be forced into the 

 chamber at one of the openings at the top (Pig. 2296, 

 c, c) and out at the bottom (Fig. 2296, f). Each of the 

 openings at the end (Fig. 2296, 



„ = ^3) is closed with a .screw cap. 



The chamber is provided with 

 tliree tin -lined copper pans, 

 fach having a narrow ledge 

 around the inside near the top, 

 which serve to hold copper rods 

 with folds of cloth, if the ex- 

 perimenter wishes to test seeds 

 according to the Geneva pan 

 method. The pans also serve 

 to hold porous saucers or 

 plates. 



The chamber when empty 



weighs about 100 pounds, and 



is therefore easily moved. 



The shelves will hold about 60 



1 1 * I. ij- blotter tests, with an equal 



a, ft, hoots for holding ,„, -, ^ ' ,. ^ t* *. 



thermometer, 6, section number of duplicates. It rests 

 of groove in chamber into upon a detachable base consist- 

 which fits c, projection on ing of a stout iron frame 15 in. 

 door; d, d, door fastener, high, inclosed with a sheet-iron 

 jacket. 

 Other Forms of Germinating Apparatus. — The so- 

 called "Geneva tester," Invented at the Experiment 

 Station at Geneva, N. Y., consists of an oblong pan of 

 galvanized iron or tin with ledges around the inside 

 near the top upon which are suspended metal rods. 

 Fig. 2298. Over these rods {y, p) is hung a strip of 

 cloth, arranged in folds, with each end of the strip 

 hanging down into the water, which covers the bottom 

 of the pan. The lower edges of the folds are sewed (as 

 at o) to hold them in place. The seeds are placed be- 

 tween these folds and are kept moist by capillary at- 

 traction; no provision is made for regulating the tem- 

 perature, the pan being placed in an ordinary living 

 room. 



Porous saucers of unglazed clay set in shallow pans 

 containing water are often used for fine seeds. Owing 

 to the difficulty of procuring clay saucers of equal po- 

 rosity plaster of Paris germinating dishes (Fig. 2299) 

 are recommended. These can be made by any one at a 

 trifling cost by means of a wooden mold, with a detach- 

 able top which consists of an ordinary pane of glass to 

 which a Petri dish is attached with glue. Fig. 2300. 



A very simple apparatus for sprouting seeds is shown 

 in Fig. 2301. It consists of a shallow tin basin "re- 

 lipped," which is given two coats of mineral paint both 



2298. Geneva seed-tester. 



inside and out to prevent rusting. The bottom of the 

 basin is covered with water, and a small flowerpot sau- 

 cer is placed inside. The seeds are laid between two 

 layers of moist blotting paper placed in the bottom of 

 the saucer, and a pane of glass covers the dish, which 

 is to be kept in a temperature of about 70° F., such as 

 an ordinary living-room. The basin may be left partly 

 open from time to time to permit exchange of air and 



SEEDAGE 



gases. By using a good-sized dish with small 



and renewing the water occasionally, several kinds of 

 seed may be tested at once at little expense. Extremes 

 of temperature and excessive moisture must be avoided. 



A still simpler germinating outfit than this and quite 

 satisfactory for most cereals and vegetable seeds con- 

 sists of two soup plates, one used as a cover, and two 

 layers of cloth to hold the seeds. The cloths should be 

 kept moist but not too wet. (See Fig. 23, Yearbook of 

 the U. S. Department of Agriculture, 1895, p. 181.) 



Temperature.— A temperature of 20° C. (68° F.) is 

 generally maintained in germination tests. Seeds of 

 celery, most grasses, and a few other species should be 

 subjected to alternating temperatures of 20° C. and 30° 

 C, the higher being used for six hours out of the 

 twenty-four. 



Duration of Germination Tests. — For purposes of 

 comparison it is desirable to have uniform periods of 

 time for conducting germination tests. The following 

 periods have been adopted in this <(juiitiy and are prac- 



tically the same as those use 

 For laboratory tests: Ti 

 spurry, peas, beans, vctil 

 beans, sunflower, l.nrl, \l:.: 

 and cow-peas; 11 lUi: 

 beet fruits, rye m:i ; i 

 lespedeza, and all i:i:(--r^ > 

 rye grass, and timuih> ; 2n . 

 muda grass. Soil tes 



2299. Plaster of Paris 

 germinating dish. 



full (lavs for cereals, 

 . l.ntils: lupines, soja 

 ! iiiit'crse, Indian corn, 

 ' -riradella, esparsette, 

 Mubelliferee, tobacco, 

 i'l i">a, Bermuda grass, 

 1 days for poa and Ber- 

 be continued two days 

 longer in each case and the sprouts counted only at the 



Special Treatment of Seeds Preparatory to Germina- 

 tion.— Soaking seeds in water for 6-15 hours before 

 placing them in the germinating chamber, as frequently 

 practiced, is to be condemned. As a rule, however, 

 seeds of asparagus, lettuce, 

 okra, and onion may be soaked 

 to advantage. Asparagus 

 should be placed in distilled 

 water for 5 hours, then trans- 

 ferred to blotters which should 

 be kept very wet for the first 

 48 hours; okra may be soaked 

 in water at 50° C. for 5 hours. 

 Owing to the readiness with 

 which moulds develop upon 

 onion seed, it should be soaked for an hour in a solu- 

 tion consisting of one part bichloride of mercury to 

 1,000 parts of water. Such seeds as okra, asparagus, 

 adonis, canna, moonflower and lupine sprout better if 

 previously clipped, care being taken not to injure the 

 germ. The loud assertions often made of the value of 

 treating seeds with certain chemicals to hasten germ- 

 ination, are, in the main, not worthy of notice. 



Testing Grass Seeds.— Most grass seeds require spe- 

 cial treatment, both in purity and germination tests. 

 For the latter neither blotters nor cloth can be depended 

 upon as a seed-bed, hence soil tests are advisable. Care 

 must be taken not to plant the seeds too deeply. Seed 

 of red-top and June grass should be sown upon the 

 surface and the lightest possible cover of soil or sand 

 given it. Before planting the soil should be thoroughly 

 watered, and after sowing a fine rose spray should be 

 used to avoid disturbing the seeds. The same remarks 

 will apply to soil tests of other fine seed. 



To prevent counting empty glumes (chaff) a mirror- 

 box (Fig. 2302) is useful. This consists of a box of hard 

 wood, half an inch thick. It is 12 in. long, 8 in. wide 

 and 6K in. high, the front being open, and the top con- 

 sisting of an ordinary pane of glass. The inside of the 

 box is painted a dead black. Attached by hinges to the 

 upper margin of the box in front is a rectangular piece 

 of black binder's board, 12 x 8 in. in size. A smaller 

 piece of similar board, 8 in. square, is attached to each 

 end of the box at its upper edge. These boards are for 

 the purpose of excluding all extraneous light. In the 

 center of the box is a mirror about 10 x 7}4 in. in size, 

 so pivoted that it can be turned at different angles and 

 reflect the light which enters the open side of the box 

 up through the glass top. 



Grass seeds are spread thinly over the surface of 

 the glass top, and the mirror adjusted so as to throw 

 the light up through the seed. The operator faces the 



