558 
Fraser. — The Development of the 
* 
ture of the fruit in its early stages differs little from that of a young 
perithecium. In both we find an outer protective sheath and a series 
of inner layers which are differentiated by their inner walls and denser 
contents. In Lachnea ere tea , as in other Discomycetes, the thinner layers 
grow upwards to form paraphyses, thrusting the outer sheath wide open ; 
but it seems probable that this arrangement is secondary, and that in 
Aspergillus and its allies more primitive. 
It remains for further investigation to determine whether all the forms 
in which a widely open fruit is produced — that is to say, the typical Disco- 
mycetes — are monophyletic, or whether they have arisen along diverse 
lines. For the moment, the value of the archicarp as a criterion is not 
quite clear. 
Possibly the most useful piece of information derived from the study of 
Lachnea cretea is the fact that the septa of the trichogyne break down. 
Pores amply large for the passage of male nuclei are formed, and thus the 
multicellular character of this organ no longer appears to impose a barrier 
in the way of normal fertilization. It is much to be regretted that this 
process was not found to occur in the material under investigation. 
In the last few years a considerable mass of literature has accumulated 
around the question of the behaviour of the sexual nuclei in the Asco- 
mycetes and the related problem of the divisions in the ascus. 
Fusion of male and female nuclei in pairs in the ascogonium has been 
described and figured in various Mildews (Harper, ’95, ’96, ’05), and, 
among Discomycetes, in Pyronema confluens (Harper, ’00) and Ascodesmis 
nigricans (Claussen, ’05). Pseudapogamous fusion of female nuclei in pairs 
has been recorded in Aspergillus repens (Dale, ’09), in Hnmaria granulata 
(Blackman and Fraser, ’06), in Lachnea ster corea (Fraser, ’07), in Ascobolus 
furfuraceus (Welsford, ’07), and in Ascophanus carneus (Cutting, ’09), and 
a corresponding fusion of vegetative nuclei, in the absence of a functional 
ascogonium, has been seen in Hnmaria rutilans (Fraser, ’08) and in Helvella 
crispa (Carruthers, ’ll), and evidence of the same process has been found in 
Poly stigma rubra (Blackman and Welsford, ’12). 
On the other hand, Claussen in Pyronema confluens (’07, ’12) and 
Schikorra in Monascus spp. (’09) have observed the association of the 
sexual nuclei in pairs in the ascogonium, but have described their fusion as 
delayed till, travelling and dividing side by side, they at last reach the ascus 
and there unite. Faull (’12) in an apogamous species of Laboulbenia has 
described a comparable state of affairs. The fusion in the ascus is regarded 
by these authors as the completion of the sexual act. 
It must be recognized that the fusion in the ascogonium maybe readily 
overlooked even in fairly large forms, but some other criteria are of 
assistance in determining whether it has occurred. 
