8i 
Nectria galligena , Bi'es. 
fresh, proved to be rather larger than the dimensions given by Wcese. 
Nectria ditissima has shorter ascospores. 
Hartig ( 21 ) describes the three main stages in the life-history, namely, 
the microspore, the macrospore, and the perithecial stages, and also found, 
as did Tulasne ( 31 ), spermagonia and spermatia on beech. The best early 
description of the fungus is given by Goethe ( 16 ), 1880, but both he and 
Lapine ( 24 ), 1892, failed to find spermagonia on apple, in spite of careful 
search. During the present investigation spermagonia or pycnidia were 
observed occasionally on apple bark affected with Nectria, but so far there 
is no conclusive evidence that the pycnidia observed belonged to N . galligena. 
This point will be more fully discussed later. Much of the work of the 
later investigators deals with the parasitism of the fungus and the effect of 
cultural and external conditions on the host and parasite, points which do 
not come within the scope of this communication. 
In N . galligena, so far as is known to the author, no investigator has 
been able to find any definite nuclear fusions, either before the formation 
of the perithecium or within the tissues of the same. Nuclear fusions have 
been described within recent years in a number of Ascomycetes, including 
a few Pyrenomycetes, such as Gnomonia ery thro stoma (6), Poly stigma 
rubrum ( 5 ), Aspergillus herbariorum ( 13 ), &c., and it was thought possible 
that a more or less reduced stage might occur in N. galligena, which so far 
had been overlooked. 
Methods. 
Portions of diseased bark and pieces of the medium on which pure 
cultures were growing were fixed in various fluids, with very variable 
results. All fixatives containing alcohol, such as acetic alcohol, formal 
alcohol, 70 per cent, alcohol, absolute alcohol, &c., were found to have 
a disturbing effect on the nuclei of the ascogonia and had to be abandoned, 
although the penetration was good. 
The only fixative that proved to be of any use for the purpose of the 
investigation of nuclear detail was Flemming’s weaker solution, and the 
time allowed varied according to the age of the perithecia to be fixed. 
Perithecia in the youngest stages on artificial media required from 4 to 
6 hours’ fixation,, whereas perithecia on bark and older perithecia on 
artificial media required longer, and could be left on the fixative 24 hours 
without harm. 
The results were very variable, in spite of the use of the air-pump. 
This is not surprising considering that tissues of extreme delicacy are 
enclosed within perithecial walls which vary in toughness according to age. 
In some cases 1 per cent, urea was added to Flemming’s weaker solution 
to hasten penetration, but the results were disappointing, and latterly 
Flemming only was used throughout. 
G 
