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the Ascocarp in Lachnea ster corea, Pers. 
It occurs in perhaps its simplest form in Boudiera (or Ascodesmis) 
(Claussen (6)), where it appears as a small upper portion cut off from the 
ascogonium, and it seems probable that the terminal cell of the coiled and 
septate archicarp in such forms as Aspergillus (De Bary (11)), Chaetomium 
(Oltmanns (19)), or Hypocopra (Nichols (18)), has or had a similar 
function. 
In Pyronemci the trichogyne, though unicellular, is better developed, 
and arises as a papilla from the growing ascogonium. 
In Polystigma (Frank (13), Fisch (12)), in Gnomonia (Frank (14)) and 
in Collema (Baur (2)), Physcia (Darbishire (9)), and other Lichens, the 
trichogyne is multicellular, and this is also the case in Poronia punctata 
(Dawson (10)), where, however, the organ is not functional and degenerates 
early. 
In these forms the terminal or receptive cell is enlarged, and to it the 
spermatia adhere. Polystigma and Gnomonia have not been found cyto- 
logically studied, but in the Lichens the cells of the trichogyne have been 
found to be uninucleate and connected together by broad cytoplasmic 
strands. 
In the Laboulbeniaceae (Thaxter (20)), both unicellular and multi- 
cellular trichogynes occur, but these form a fairly complete series among 
themselves. 
It will be seen that the trichogyne of Lachnea ster corea, consisting as 
it does of a series of coenocytic cells, the terminal of which is considerably 
larger than the others, is intermediate in structure between the trichogyne 
of Pyronema on the one hand, and that of such forms as Physcia 
and Collema on the other. It differs also from the latter in the fact 
that its constituent cells are not visibly connected by strands of cyto- 
plasm ; such connexions may or may not have existed when the organ was 
functional. 
L. ster corea, in the general structure of its ascocarp, in the organization 
of its large coenocytic ascogonium, and in the character of its male organ, 
resembles Pyronema much more closely than it does any of the Pyreno- 
mycetes. But if L. ster corea be supposed to have arisen from such a form 
as Pyronema, it is difficult to imagine to what conditions the septation of 
the trichogyne was a response. 
It may be that the close relation of the ascogonium and antheridium 
in L. ster corea was a late modification, and the multicellular structure of 
the trichogyne may have given it greater stability in reaching out towards 
a male organ developed at a distance. In Pyronema, however, the anthe- 
ridium arises separately from the archicarp, and yet a unicellular trichogyne 
serves to connect the two. 
On the other hand it has been held by Thaxter (20) and others that 
the Ascomycetes may be derived from the Red Algae, through some such 
D d 
