16 



Mycologia 



This plant is a favorite with the rodents — the wood rats search 

 for it persistently. I have been able to detect it a long distance 

 on a quiet day when the odor penetrates the woods while rats eat 

 it. Proving this to a skeptic this last season afforded much 

 amusement, and also added proof of its qualities. A visitor 

 accompanied me on one occasion in May to this region, and in 

 the woods I soon detected this odor and called attention to it. It 

 was so strong that my friend noticed it, and was able to work 

 down wind to its source under my direction until I pointed out 

 the freshly turned ground and leaves. I induced him to dig 

 among the leaves and he soon found tht Melanogaster. It seemed 

 almost unbelievable that such a small object could be so pungent. 



On this latter occasion, I secured in the debris of a rat's nest 

 a different species, larger, and covered with a very dense golden 

 to reddish powder. Since then I have gathered two additional 

 species, none with the evil odor. The different species are easily 

 distinguishd by their reaction in alcohol, the former turning a 

 deep eosin-red, and the others changing according to the color of 

 their powder or spores. 



Referring to these strong odors so characteristic of the Hyme- 

 nogastraceae, I have found other genera very offensive when car- 

 ried about in a collection, and this is true particularly with 

 reference to species of Hysterangium, while Rhisopogon and 

 Gautieria are also reported as very powerful. But some species 

 are negative or mild ; at least one Gautieria is very pleasant and 

 others are bad only after being confined in a collecting case. Both 

 the Hysterangium and the Gautieria are favorites of the wood 

 rats, and the smell is easily identified at a long distance when the 

 rats are feeding upon them. 



Still in a persistent search for truffles, and loath to give up my 

 location at Guadaloupe and seek other ground, I renewed my 

 quest two days after finding the first Melanogaster in that vicin- 

 ity. This took me into the very heart of a dense manzanita 

 thicket, where progress was upon hands and knees. I shortly 

 became involved so completely in the tangle that further progress 

 was impossible- I came to a stop at a huge rat's nest built around 

 an enormous manzanita, and had actually seen the occupants dig- 

 ging for some fungi around its very base. There was noticeable 



