Weiss.— A Mycorhiza from the Lower Coal-Measures . 263 
with those of the Fungus in recent mycorhizae will, I think, be regarded as 
sufficient evidence for the conclusion that we are dealing in the case of this 
fossil plant with a mycorhiza or my corhizome. The Fungus differs materially 
in its manifestations from other cases of endophytic Fungi so far observed 
in fossil plants, and in no way suggests that it was living either sapro- 
phytically or parasitically upon the host-plant. The excellent preservation 
of both the Fungus and the host-plant and the specialization of the cortex 
into two layers comparable with the ‘ Pilzwirthzellen ’ and £ Verdauungs- 
zellen 1 of recent mycorhizae, would suggest that, as in the case of the 
latter, the host-plant is deriving some benefit from the presence of the 
Fungus. 
We cannot of course expect from the investigation of a fossil mycorhiza 
to elucidate the difficulties that surround the mycorhiza-question, but 
it is of no little interest to find that already at the Coal-Measure period 
Fungi and cormophytes exhibited a mutual adaptation of such com- 
plexity as that involved by the formation of a mycorhiza. 
Of the systematic position it is difficult to say much on the slender 
evidence before us. I have not been able, in any of the longitudinal 
sections, in which one sees occasionally considerable lengths of the Fungus, 
to detect any transverse walls, and this would incline me to the belief 
that the Fungus belonged to the group of Phycomycetes. This view would 
be supported by the fact stated by Seward (’98), that the Phycomycetes 
certainly existed in Permo-Carboniferous times. Among recent endo- 
phytic Fungi showing symbiotic adaptation some apparently also belong 
to this group, according to Bruchmann (’85) and Goebel (’87). 
The systematic position of the host-plant is almost as difficult to 
determine as that of the Fungus. Leaving out of consideration the 
Gymnosperms and Cycadofilices with which it shows no affinities, we may 
confine ourselves to the consideration of the Vascular Cryptogams. Of 
the four divisions of these it seems, as mentioned above, to have most 
affinity to the Lycopodiales, though it differs considerably from most 
of these. It has not the specialization of the cortical tissues characteristic 
of the Lepidodendraceae and, if it is a root, does not possess the usual 
monarch arrangement found in that group. The absence of large inter- 
cellular passages such as are found in the roots of Lepidodendraceae and 
Calamarieae would lead us to infer that it was not rooted in marshy 
ground as were probably these larger fossils, and its association with 
a P'ungus would rather point to a saprophytic existence in rich leaf- 
mould or to an epiphytic existence like that of Tmesipteris on the stems 
of Tree-ferns. In either case it would be likely to become infected 
with fungal hyphae, and might develop the special adaptation which its 
mycorhiza exhibits. That a mycorhiza has not been found in other 
Coal-Measure plants should not astonish us when we remember that 
T 
