BRIEFER ARTICLES. 
Abnormal fruiting of Vaucheria. (WITH PLATE xxI.)—In specimens 
of Vaucheria geminata, var. racemosa, brought into the laboratory in 
October, 1894, some interesting cases of abnormal fruiting organs 
were observed. The material was collected in the grassy flats of 
Cayuga lake, at a spot covered by the overflow of a small stream. 
The variations from the normal were frequent, and included three 
general types: 
1. Those in which the oogonia were aborted, leaving on the fruiting 
branch stump-like protuberances. 
2. Those in which the oogonia were prolonged into vegetative fila- 
ments. 
3. Those bearing fully developed antheridia in places normally oc- 
cupied by oogonia. 
Numerous combinations of these types with different intermediate 
forms were also present. 
The first case is inconspicuous, and admits of some doubt, inas- 
much as the stumpy protuberances closely resemble branches from 
which oogonia have fallen. In certain specimens, however, the pe- 
culiar shape of the end of the stump, its unusual length, and the entire 
absence of any trace of a broken sheath, such as is usually left by a 
fallen oogonium, furnish conclusive evidence that the female organ 
has not been present. Whether the rudiment represents an oogonium 
or an adventitious antheridium, such as is described in type three, it 
is impossible to determine. 
The second type shows close analogy to conditions found in differ- 
ent fungi, notably the Saprolegniacez. The vegetative filaments arise 
sometimes from the apex of an oogonium, sometimes directly from 
the pedicel, thus replacing the oogonium. They are usually narrower 
than the mother filament, but in cases which seem to be intermediate 
between this and the first type, the young filaments have a diameter 
equal to that of the pedicel from which they arise. Different forms 
of this type are described and figured by Campbell in the American 
LVaturalist for June, 1886, from observations made on artificial cul- 
tures. 
The third case presents a somewhat more remarkable condition, but 
one to which a partial analogy may be found in ferns, where rudi- 
mentary prothallia, from crowding or insufficient nutriment, produce 
only antheridia, Reasoning from this analogy, we are led to assume 
that the filaments of Vaucheria upon which such fruiting organs are 
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