Parks : California Hypogaeous Fungi 



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Tuber candidum is the most commonly collected and widely dis- 

 tributed truffle in this State. It is particularly abundant in some 

 seasons in wet clay soil at the Guadaloupe Mines, generally under, 

 the live oaks, but frequently under other trees. It appears late in 

 the winter and continues into the late spring or early summer. 

 April and May seem to produce the greatest amount of mature 

 plants. In places where it is collected in abundance one year it 

 seems to be three or four seasons before it occurs in any large 

 amounts again. The ascocarps are very smooth, pale brown or 

 with a slightly pinkish color, or sometimes, when young, of a dark 

 gray. It is variable as to color and shape. Generally globose or 

 with two or three large, lobes, it is sometimes found with deep 

 furrows traversing the surface; occasionally it * is cracked to a 

 depth of several millimeters. The peridium is thick, the gleba is 

 at first white, turning to a pale purple color and finally a rich 

 brown, with a tinge of yellow as it reaches maturity, and the 

 yellow spores fill the tissue. The asci may be seen for a long time 

 during the development of the ascocarp, but the spores are slow to 

 mature. In the middle of March I examined a certain piece of 

 ground and found it barren. Two weeks later I collected a pint 

 of mature specimens in it, and repeated two weeks later with some 

 very large specimens. At the next visit, two weeks later, nothing 

 was to be seen but a few empty peridia left by the slugs. 



Plants are rarely on the surface of the soil, but are just beneath 

 and down to a depth of several inches, and are easily raked up, 

 but care must be used to avoid damaging them or missing them 

 altogether if they are not abundant. Usually they are rather con- 

 spicuous if reddish brown, but if very pale or dull gray they are 

 hard to find. Frequently single plants appear over wide areas, 

 but generally they are in considerable numbers in a small area. 

 They frequently are found in clusters of three or four plants, 

 appearing to arise directly from the spores without any great 

 mycelial growth. 



The mycelial growth seems to be very scant and the plants show 

 no basal point of attachment. Many specimens show where loose, 

 fine hyphae traverse the surface of the ascocarp, but these disap- 

 pear when the plants are removed from the ground. The dis- 



