v/a) 
8 
Almond integuments (prepared as above).—H. No. 1 gave a dense, black 
mycelium and abundant conidia. 
Corn meal (moistened and autoclaved in test-tubes)—H. No. 1 gave 
dense, black borders and greenish-black interstices. 
Corn-starch (prepared as above).—H. No. 1 gave a dense, black, even 
surface-growth with little or no aerial mycelium. 
SUMMARY CONCERNING GROWTH ON RICE AND SIMILAR 
SUBSTANCES 
With Helminthosporium, as with Fusarium, rice tubes are of value for 
differentiating species. The important constituent seems to be in the 
aleurone layer. Pearl-barley has similar and different, though less, value. 
Whole wheat grains, whole rice, beans, etc., do not give these color reactions. 
Color phenomena in fungi have been discussed by Smith (106), and 
Hedgecock (65), and by Stewart and Hodgkiss (119), who cite several 
papers bearing upon the subject. These, however, deal mainly with 
conditions of acidity and general carbohydrates rather than with proteid 
relations.* 
MISCELLANEOUS VEGETABLE MEDIA 
Parts (plugs) of various vegetables were placed in test-tubes—in 
some cases with glass slips—with about 2 c.c. of water and autoclaved. 
The chief- resulting characters of various Helminthosporium plantings 
on such media consisted in the development of aerial mycelium and 
the pellicle over the surface of the water. 
Potato plugs (prepared in the usual way)—H. No. 1 gave on these 
plugs large development of woolly, white aerial mycelium. At the line 
of contact with the glass the growth was dense and black. No sclerotia 
developed in four days. This medium possessed little differential value, 
only H. Nos. 11, 12, and 17 showing clear differences. 
Potato plugs on glass slips —The slips were placed in test-tubes (in 
the manner shown in Fig. 2, page 95), and then slices of potato, which were 
so cut that they could barely be crowded into the tubes. They were then 
autoclaved. This gave opportunity for observation at three places: (1) the 
exposed potato surface; (2) the contact of the potato with the glass slip and 
with the wall of the tube; and (3) the border at the edge of the contact 
(cf. with terms under rice, p. 86). H. No. 1 here gave a dense black 
*In this connection see paragraph on carbohydrates on ,1ge 100. 
