Some recent work on the cytology of fungus reproduction 
207 
remains constantly eight, and that the processes of division agree ab¬ 
solutely with those in all the other Ascomycetes he has investigated. 
Brown (1911) has studied the development of the ascocarp of 
Lachnea scutellata. The archicarp, when mature, consists of a row of 
about nine cells which reminds one of the scolecite recorded in some of 
the Ascobolaceae , though there seem to be no pores in the septa of the 
archicarp. In this connection one may notice that the speciecs in which 
Woronin first described the scolecite, namely Ascobolus fiulcherrimus, has 
been placed in the genus Lachnea by certain authors e. g. Cooke, Gillet, 
Saccardo. 
The nuclei in the ascogonium divide karyokinetically, centrosomes 
being present. “Five daughter chromosomes proceed to each of the 
opposite poles .... The two groups of chromosomes are usually sepa¬ 
rated far enough so that when they reorganise the daughter nuclei are 
separated by an appreciable distance. Frequently, however, the daughter 
nuclei reorganise so close together that after a slight growth they are 
pressed against each other and resemble fusing nuclei.” The nuclei do 
not divide simultaneously and all stages can be found in a single asco¬ 
gonium. No fusion of uuclei was observed in the ascogonium. In a 
number of cases nuclei were seen pressed against each other but in 
every case the nuclear membranes between the nuclei were intact 
and every appearance suggested that the two nuclei were daughter 
nuclei of the same nucleus which had reorganised close together. Also 
fusion nuclei are often simulated by the fact that during prophase, when 
the nuclei are large, the chromosomes sometimes mass into a nucleolus¬ 
like group. “It may be said that a fusion of the nuclei would be hard 
to find, but they have been looked for very carefully in a large number 
of well fixed and stained preparations. The slight decrease in the size 
of the nuclei during the development of the ascocarp and the persistence 
of the same number of chromosomes throughout the ascogonium and 
ascogenous hyphae, moreover, indicate very strongly that a fusion of 
nuclei during this stage is not to be expected.” The first division in the 
ascus is heterotypic, the second and third divisions are of the same type 
as those in the ascogonium. The number of chromosomes is five in all the 
nuclear divisions throughout the life history of the fungus and there is 
thus no second reduction. The author’s figures of the nuclear divisions 
are all text figures and it is very unfortunate that all those which deal 
with the division in the ascogonium, the critical portion of the paper, 
should be labelled “X 11,200”. (Fortsetzung folgt.) 
Referate. 
KNOLL, F., Untersuchungen über den Bau und die Function der 
Cystiden und verwandter Organe. (Jahrb. f. Wiss. Botanik, 1912, 
50 , 453—501, Tafel VI.) 
Die Fruchtkörper vieler Hymenomyceten besitzen eigene Organe 
für die Absonderung von Wasser in tropfbarflüssiger Form (Hydathoden) ; 
dieselben können an der sterilen Oberfläche des Fruchtkörpers, aber auch 
