6888 BOTANICAL GAZETTE [FEBRUARY 
of 12 per cent. to 37 per cent., @,; for an attraction of 37 per cent. 
to 62 per cent., @,; etc. An interrogation point indicates a value 
near the lower limit of the class indicated. 
This method was used in the preliminary testing of a large number 
of representative chemical substances with Sterigmatocystis nigra 
and Mucor mucedo; Botrytis villgaris was used with a few that gave 
decided effects. The series included the sulfate of sodium, of 
magnesium, of calcium, of ammonium, of potassium; the normal 
phosphate of ammonium, of potassium; the dibasic phosphate of 
ammonium, of potassium; the monobasic phosphate of potassium, 
of sodium, of calcium; the chlorid of potassium, of ammonium, of 
calcium, of magnesium, of sodium, of lithium; the nitrate of potas- 
sium, of ammonium, of calcium, of magnesium, of sodium; the 
oxalate of magnesium, of potassium; the tartrate of magnesium, 
of potassium, of sodium-potassium; the bitartrate of potassium; 
the lactate of magnesium; the malate of magnesium, of ammonium; 
the acetate of potassium; acetic, lactic, tartaric, malic, oxalic acids; 
cane sugar, dextrose, galactose, maltose, lactose, starch; glycerin, 
ethyl alcohol; active pepsin, boiled pepsin, trypsin, peptone, mannit 
agaricin, casein, asparagin, urea; meat extract, beet decoction, bean 
decoction, distilled water; mercuric chlorid, copper-sulfate, copper 
acetate, lead nitrate, zinc nitrate, iron sulfate, iron chlorid, potassium 
ferrocyanid. In the case of such of these compounds as were tested 
by MrvyosuI, concentrations were used that would give the maximum 
effect of attraction or repulsion. With nearly all compounds two, 
and with many three, concentrations were tested. 
The hyphae showed a tendency, in small numbers, to turn toward 
the tubes in the majority of tests; but in only a few instances were 
more than about 37 per cent. of the hyphae in the observed area 
TABLE I 
A se S S $ in > = s, Ss} tid “J 
Pe ra S| dé le le le BS) BS [gael gS 
SPECIES Eacl S| | 3 FaaclZacl“ac| “nel Sas] J |. les 
a} O |O hse Fa|.8 Mo a\e8 g au 4 
SSIS [g lg Bs) & geige 
o ae < a BAW l< 
Sterigmatocystis nigra.......... Fire . Po a ee ps r 
Mucor mucedos. Yoav eeu: jvc) Qe fest 4 ae lect YF | Bel ae) Ax] Bat Oa) Se 
Botrytis vulgaris... cic. es cok fla [ocebessdeks 
r ily te SEAS Bi nee banca lear ae 
ee : Pe RSS ae x bigest uted 
a a eI Te fee IB ine hy, S He ne REN é i 
