1890.] NEW-YORK MICROSCOPICAL SOCIETY. 83 



De Bary has relegated it "to the history of errors," the notion is 

 not extinct that the aerial mold Empusa is but a condition of the 

 aquatic mold Saprolegnia. 



This cup-like plant is surmounted by a lid or operculum, very 

 suggestive of that to the capsule of a moss. It lacks the sym- 

 metry of the latter — being sometimes a relatively short cone, 

 and at other times quite long. The rim or edge of the cup is 

 inflected, so that the aperture into which the lid fits is not nearly 

 so wide as the diameter at the face. Over this opening sits the 

 operculum, thus giving the appearance of two funnels, with their 

 apertures facing each other, the smaller one being uppermost. 



The above is the position until fructification is complete, 

 when the sporidia become a heap, rising into the operculum or 

 cap, and lifting it up and off. They are now a spore-swarm, and 

 as such are quite large when compared with the size of the 

 parent thallus, but individually they are so small that a magnifi- 

 cation of about 900 diameters gave only limited details of 

 structure. 



It thus appears that the thallus, or entire plant is a mother- 

 cell or capsule; in fact I believe it is a compound sporangium. I 

 have seen numbers of these emptied capsules open or split down 

 one side, from the aperture. These seeming rents revealed lines 

 irregularly parallel, and lengthwise of the sporangial capsule. 

 These are each attached by one edge to the inner wall of the 

 capsule like the gills in the pileus of a mushroom, or any 

 agaricoid fungus. These laminae do not reach across the cap- 

 sule; thus they form a well-like space under the opening or out- 

 let which is covered by the cap or operculum. It seems to me 

 that the spaces between these laminae serve for sporific or quasi- 

 hymeneal planes, from which the sporidia are discharged into 

 the central part, or well of the sporangial capsule, and thence 

 like a little cloud they swarm as zoospores at the outlet, that is, 

 over the edge of the cup-like mother cell. 



As noted in our first paper a distinguishing trait of the Sap- 

 rolegnice, is the issuance from the sporangium of the zoospores, 

 or motile spores. It seems tome that these swarms of this marine 

 fungus must consist of motile sporidia. But on two points we need 

 light — the history of the spore development or complete fruition 

 — and assured knowledge in respect to the absence or presence of 



