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FROMME, F. D., Sexual fusions and spore development of the flax 
rust. (Bull. Torrey Bot. Club, 1912, 39, No. 3.) 
Fromme has worked at Melampsora Lini an autoccions eu-form 
attacking Linum usitatissimum . The frequent intimate association between 
the spermogonia and aecidia is an interesting feature, the two often 
being separated only by the outer sterile layers of the spermogonium 
and developing simultaneonsly. 
The spermatia are produced on septate branching spermatiophores. 
It is suggested that this branching of spermatiophores may furnish a 
further basis for use in the Classification of the Uredineae . 
The fusing cells at the base of the aecidum are quite similar. The 
abundance of sexual fusions in this form is most striking some sections 
showing every pair of gametes in the sorus in some stage of fusion. Two 
short sterile cells are normally formed above each gamete. Their function 
is evidently protective and Fromme suggests that they may correspond 
to the pseudoparenchyma of young aecidium cups. 
In addition to the normal two-cell fusions, fusions of three and four 
cells have been found: it seems that this might be regarded as further 
evidence that the sexual processes as found in the rusts, are of a secon¬ 
dary character. Large multinucleated cells are also present in the same 
sorus with two-, three-, and four-cell fusions. J. Ramsbottom (London). 
BULLER, A. H. R., The production and liberation of spores in 
the genus Coprinus. (Trans. Brit. Mycol. Soc., 1911, 3, 348—350, 
Worcester 1912.) 
Buller in this paper gives a resumé of his work on Coprinus . 
Coprinus atramentarius , C. narcoticus, C. stercorarius and C. macro - 
rhizus possess cystidia: C. comatus and C. sterquilinus do not. In the 
first group of species the cystidia serve to keep the delicate gills apart, 
so that the spores on hymenial surfaces of adjacent gills are prevented 
from touching one another during development. In the second group, the 
separation of the gills is provided for by the free margins of the gills 
which are swollen into sterile bands or flanges. 
The successful liberation of the spores from the parallel-sided gills 
of C. atramentarius is brought about by special adaptations the chief 
of which are: 1. The spores ripen in a progressive zone from below 
upwards on each gill. 2. The spores are discharged in succession upwards 
on each gill. 3. The spore-freed portions of the gills, as soon as they 
have come inte existence, are destroyed by autodigestion. 
Definite, constantly-occurring, paraphyses are present in the hyménium 
of Coprinus , which function as special agents preventing the spores of 
adjacent, simultaneously-maturing basidia from touching one another. The 
basidia of most species of Coprinus are dimorphic. This allows of closer 
packing. The long basidia often discharge their spores a short time before 
the immediately-adjacent short basidia. The spores of the short basidia, 
at the time when they are shot out into the interlamellar spaces, are thus 
prevented from colliding with the spores of the long basidia. The basidia 
are more or less trimorphic in C. micaceus. 
