Notes on Fungi. I

W. G. Farlow
1889 Botanical Gazette  
In my paper on Peronosporee (BOTANICAL GAZETTE, viii. 335), the statement was made that the Cystopus parasitic on Convolvulacec in the United States was apparently the same as the JEcidiuzm Ipomwce-pandurane of Schweinitz, Syn. Fzung. Car. Sup. no. 454, and a doubt was expressed as to whether it should be united with the C. cubicus (Strauss) Lev. which infests Composito, although the conidia of the two forms are much alike. At that date the oospores of the form on Convolvulacec had not been
more » ... ec had not been seen, and I suggested that they should be sought in the stems and petioles rather than in the leaves. In the autumn of I888 I received from Prof. L. H. Pammel some very interesting specimens of swollen stems of Ipomca landurata, collected at Valley Park, near St. Louis, Mo., in which he had found the oospores in abundance, while the accompanying leaves were covered with conidia. The swellings of the stems were very striking, and in one fine specimen the tumor formed by the hypertrophied parenchyma of one side of the stem was six inches long and somewhat over an inch in diameter, while the stem itself, whose diameter was not greater than a quarter of an inch, was bent over in the form of a horse-shoe by the growth of the unilateral tumor. The surface of the tumors when fresh was continuous, but in drying they cracked open and the inner portion was exposed in numerous places. Microscopic examination showed that the oogonia were different from those of any other Cystopus known to me, since their walls were not smooth, but raised in blunt papilla, or short flexuous ridges over their whole surface. In the younger oospores the smooth-walled antheridia were in marked contrast with the papillate oospores, and the pollinodia were larger and more prominent than in other Peronosporece, so that the present species is remarkably well adapted for the study of the fertilization in this order. The oogonia are very irregular in shape, appearing in some sections nearly triangular, and their average diameter is 45P/. The oospores are on an average about 36/i in diameter, with an endospore 3ft thick. The This content downloaded from 131.172.036. 1889.] BOTANICAL GAZETTE. I89 Alabama. The leaves were sent to me as cotton leaves, to which they bear a strong resemblance, but a microscopic examination shows that they can not be cotton leaves, but probably leaves of some Ipomoea or Convolvulus. The date of the original Schweinitzian name is 1822, which must be prior to any name of Otth, even if I am mistaken in supposing the name cited by Zalewski to be merely an herbarium name of Otth. In 1834 Schweinitz in Syn. Fung. Am. Bor. no. 2866 changed his original name to Ceoma Convolvulalum, and in Grevillea, iii. 60, Berkeley and Curtis enumerated zEcidium Ifomnce Schw. on I. trichocarpa, the same as I. commutata mentioned above. IEcidium Ipomceae is apparently an abbreviation of the name in the Syn. Fung. Car. In the Sylloge, vii. 67I, Berlese and De Toni give Azcidium Ipomcae-panduranae as a synonym of Puccinia 5ponomce Cke., based on the specimen in Ravenel's Fuing Americani, no. 792. This is an error, for the aecidium in the specimen named is certainly not the true LEc. Iipomoee-tandzrance of Schweinitz, but what is called by Cooke, in Grevilea, xiii. 6, zEczidium Convolvuli Schw. var. Ipomcece. In this connection it may be said that Cystopus cubicus has been found on Matricaria at San Diego by Mrs. Eigenmann, and on Perityle Californica, var. nuda, in Lower California. The last named specimens, received from Mr. Colville, contained ripe oospores. Last autumn I received from Mr. K. Miyabe a very interesting Peronospora, found by Mr. Y. Tanaka on Cucumis sativa in the preceding June at Minoma, Tokio, Japan. The dried material received was accompanied by some excellent drawings, showing not only the conidia, but also illustrating the germination, which was by means of zoospores. The Peronospora hitherto known on Czcurbilacece in the United States is P. australis Speg., P. sicyicola Trelease of my previous paper. In the Sylloge Fungorum P. australis and P. sicyicola are described separately, but there can be no doubt that they are the same species, since not only does Spegazzini's excellent description answer to our plant, but specimens which were sent to him were pronounced by him to be certainly the same as the South American plant. The germination of the conidia of P. australis has not been seen, but the pinnate branching and condensed spiny tips of the conidiophores, and the general character of the spores are so much like those of such species as P. viticola and P. Halstedii, which are known to produce zoospores, that it might be supposed that it would also produce zoospores. This content downloaded from 131.172.036.
doi:10.1086/326436 fatcat:ahsuyt64lnbznmed42wcqhufce