MONOGRAPH OF CHAETOMIUM AND ASCOTRICHA 517 
brown or black, irregular pustules, with here and there stiff, dark 
bristles near the margin of the pustules. It has little resemblance 
to a Chaetomium. Mounts of authentic specimens of Ch. 
laeliicola, to which Saccardo (85, р. 429) has later referred as 
Ch. laeliicolum, show the plants to be in the form of irregular 
pustules erupted through the epidermis of the host, from which 
arise stout, dark, septate hairs. Sections of the same material 
show the fruiting bodies to be sunk deeply below the surface of 
the tissue of the substratum on which they grow. 
Іп 1900 Cocconi (15) gave the name Ch. papillosum to а 
plant which he found on rotting wood in a field at Bologna, and 
which resembles a Magnusiella in certain of its characteristics, 
and Ch. murorum Cda. in others, yet differs from both in some 
respects. He described and figured this form as having a small, 
globose perithecium, perforated at the apex by an ostiole, and 
with hairs diverging in all directions. At the apex the peri- 
thecium was rather scantily supplied with abruptly incurved 
hairs. The asci were cylindrical, with their spores arranged in a 
single row. According to Cocconi experiments with cultures of 
this plant demonstrated on the one hand the formation of a 
Pycnidial stage which produced two-celled spores, and on the 
other, the formation of branched conidiophores bearing spores 
in a clump at the tips of the branches. 
In 1902 Massee and Salmon (59) published a diagnosis of Ch. 
arachnoides. At first sight mounted specimens of this form, 
which were received from the Royal Botanic Gardens at Kew, 
may be easily mistaken for а Chaetomium, but with more careful 
€xamination characteristics appear which are sufficient to exclude 
it from this genus. At the top of the perithecium is a long neck 
resembling that of a Melanospora, and it is from the neck that 
the hairs arise which form at maturity a tangled mass, and which 
Closely resemble the hairs of Ch. murorum Cda. The spores 
at maturity are honey-yellow in color, a characteristic unusual 
for Chaetomium spores. 
There are three scattered nomina nuda which have been 
found in literature unaccompanied by description or figures, and 
regarding which little is known. Material under the name of 
Ch. Bromelliae Schw. has been found in the Curtis herbarium, 
