Butler.—On Allomyces , a new Aquatic Fungus. 1033 
its sexual organs resembles that found in several Leptomitaceae, but 
fertilization is effected by 2-ciliate spermatozoids, and so far as is known 
resembles the process in Vaucheria. The asexual reproduction is so far 
only known through the formation of ‘ gemmae ’, which are held to be 
sporangia reduced to conidia as occurs in the higher Phycomycetes. 
While, therefore, it is not safe to be dogmatic in regard to the origin of 
the Oomycetes, the discovery of new forms [Dichotomosiphon , Allomyces ) 
strengthens the old view of their derivation from the Siphoneae. Only by 
further discoveries can this view be proved or disproved. Perhaps also the 
equally obscure question of the origin of the Chytridiaceae can only be 
solved in the same manner. 
Summary. 
In the above paper a description is given of an Indian aquatic Fungus, 
Allomyces arbuscula , n.g., n.sp., belonging to the family Leptomitaceae of 
Schroeter. It is an aberrant member of the family, inasmuch as it has 
a completely segmented thallus. Its nearest ally is probably Blastocladia , 
and with this genus and Gonapodya it constitutes a group of forms with 
non-cellulose walls and predominantly i-ciliate zoospores. This group is 
believed to show decided indications of affinity to M'onoblepharis , the 
peculiar resting spores of Allomyces and Blastocladia in particular being 
held to be parthenogenetically developed oospores derived from the 
Monoblepharis type. The Leptomitaceae are probably a more primitive 
family than either the Saprolegniaceae or Pythium , and have perhaps been 
derived through forms resembling Monoblepharis from the Siphoneae 
amongst the green Algae. 
LITERATURE. 
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