The Panama Disease. 
BY 
Ed. ESSED, B.Sc. (Edin.). 
With Plate XXIX. 
II 
T HE research was continued in order to control the results obtained at 
first and to study the development of the fungus in detail. The 
results are such as to enable me to add more particulars concerning the 
at first puzzling pleomorphism, and to elucidate and slightly correct some 
statements made in my first paper. 
Sclerotia. As such were described structures arising from single 
hyphae, or even parts of them, whereas a true sclerotium is a structure 
formed by the interlocking of a number of hyphae, which give rise to 
a pseudo-parenchyma, often with distinct cortical and medullary parts. 
Resting mycelia is a useful general term ; but it appears to me preferable 
to use a special term for a definite structure : in this case I propose to use 
the term pegmatium to indicate structures arising from well-nourished 
hyphae, or even portions of them, which passing or not through a stage 
of slimy dissolution of their walls, harden into gristly or gummy bodies 
having the power to regenerate the fungus mediately by chlamydospores 
— into which they break up under favourable conditions — or immediately 
by mycelia arising from them without the interposition of a spore stage. 
These pegmatia are found to consist of a sterile and a fertile part ; 
the first one, hard and gummy, is derived from the hyphal walls ; the 
latter, more or less gelatinous, from the protoplasmic contents of the 
hyphal cells. For the sterile part I wish to introduce the term mycoporoma , 
and for the fertile part the term myclomyxa. 
Pegmatia. In hyphae from which some pegmatia arise, the proto- 
plasmic contents are seen to break up into numerous globules, spore-initials 
apparent by their greenish opacity. In the one case the cell-walls then 
begin to thicken and gradually pass to a gelatinous substance, in which the 
spore-initials are hardly perceptible ; they become quite indistinct as soon 
as the mass begins to harden and to assume a yellow to brown hue. In 
[Annals of Botany, Vol, XXV. No, XCVIIJ. April, 19m] 
