24 
HABITATS 
elects to flourish on a matrix very different from that on 
which it usually occurs. A very curious case in illustration 
of this was the discovery of Lachnea sublivida (first British 
record) by Mr. Charles Crossland on a very thin layer of 
black dust covering some pig-iron in a foundry at Hebden 
Bridge, Yorkshire, its usual habitat being damp soil. 
There are old records of fungi occurring on iron which 
had been red hot only a few hours previously. It is possible 
that these concern species of Mycetozoa which had migrated 
to the iron soon after it had cooled. 
Dr. Plowright once found Pleurotus ostreatus growing on 
dry cerebral matter in the skull of a stranded whale on the 
Norfolk coast. 
Peculiarities of environment sometimes totally change the 
appearance of a species, and produce a monstrosity. Absence 
of light is one of these. Certain 
Hymenomycetes assume most 
grotesque shapes when growing 
on timber in mines— e.g., Lentinus 
tigrinus and Polypovus squamosus in 
such situations occasionally re¬ 
semble the branched antlers of a 
deer. 
Abnormal growths, the causes 
of which are unknown, are not at 
all uncommon. Fig. 6, B, de¬ 
picts the monstrosity “ tortilis ,” of 
Clitocybe laccata. The pileus forms a closed ball, on the 
greater part of which the gills form an anastomosing 
network. 
Fig. 6. 
A, An agaric with secondary pileus ; 
B, Clitocybe laccata —monstro¬ 
sity “tortilis.” 
The innate tendency amongst certain Hymenomycetes to 
secure a protected hymenium has been already alluded to. 
It may also be seen in species which, through accident of 
position in youth, find themselves growing stalk uppermost. 
I once found a specimen of Hydnmn repandum growing head 
