SHOWING STRUCTURE, FROM THE RHYNIE CHERT BED, ABERDEENSHIRE. 867 
of the genus Palseomyces. This generic name is employed in the comprehensive 
sense suggested by Seward. # Some of the other types figured may be grouped, on 
grounds of general resemblance that does not imply specific identity, in relation to 
those few to which we venture to give names. 
The forms which we thus propose to name may be indicated by reference to the 
numbers used in the preceding descriptions. The specific characters can then be 
summarised in diagnoses. 
The name Palseomyces Gordoni will be given to the well-marked and widespread 
form described as Fungus No. 2 above. The specific name is given to mark the 
association of Professor W. T. Gordon with the study of the Rhynie chert. As 
recorded in Part III, we owe to him the unique block of chert containing what we 
assume to be the reproductive organs of Asteroxylon. Under this name also, as 
P. Gordoni var. major , the form with similar but larger resting-spores, described 
as Fungus No. 3 above, may be placed. We may further associate with this species 
the forms which we do not name, but have distinguished as Fungus No. 1 (hyphal 
strands) and Fungi Nos. 4 and 5 (thick-walled resting-spores of smaller size). 
The name Palseomyces Asteroxyli will be given to Fungus No. 7, which is so 
commonly and typically present in the more or less decayed inner cortex of the 
rhizomes of Asteroxylon. Some other forms with fairly stout hyphse enlarging into 
vesicles ( e.g . Fungus No. 6) may perhaps be associated with this without placing 
them under the same name. 
On similar grounds, both of structural features and of regular position of occur- 
rence in some rhizomes and stems of Hornea, the form described as Fungus No. 8 
above may be named Palseomyces Hornese. 
There is considerable variety in the forms with relatively small resting-spores 
or vesicles borne on fine hyphse. We shall only distinguish and name three 
of these. 
Fungus No. 9 will be named Palseomyces vestita. With this we might associate 
forms that are occasionally met with, and have their larger thin-walled spores 
sometimes covered in the same fashion by fine hyphae. 
The peculiar and insufficiently known form with hyphae bursting the surface 
and terminating in associated pear-shaped vesicles (Fungus No. 13) will be named 
Palseomyces Simpsoni, after Mr Simpson, who noticed it and kindly sent us his 
preparation for study. 
The name Palseomyces agglomerata is given to Fungus No. 10 as the most char- 
acteristic and repeatedly occurring form with fine hyphae and thin-walled spherical 
resting-spores. With this may be associated more or less closely, but without 
bringing them under the same specific name, Fungus No. 11 and Fungus No. 12. 
Further, the various types of fine mycelium described as Fungus No. 14 and Fungus 
No. 15, and found as intrusive fungi in the large resting-spores of Palseomyces 
* Fossil Plants, vol. i, p. 222. 
