New stations for Physoderma and Ligniera 



[. S. K IKLING 



In the summer of 1933 while collecting aquatic plants, al- 

 gae and funiji in the vicinity of New York City the author 

 encountered a species of Physoderma and two of Ligniera, which, 

 as far as he is aware, have never been reported from this par- 

 ticular locality. Physoderma zeae-maydis was found fairly abun- 

 dant on maize in a small field a short distance from the railway 

 station at Cold Springs Harbor. Long Island. According to 

 Lyman (1918) and Tisdale (1919) this parasitic chytrid ha> not 

 been observed along the Atlantic coast further north than south- 

 ern New Jersey, and its presence on Long Island suggests at 

 least that it may have a more extensive distribution than is 

 generally suspected. It grows readily in the leaves and sheaths 

 of corn in New York City, as has been shown from inoculated 

 garden plots at Columbia University, and it is not improbable 

 that during the summer months it may extend into New Eng- 

 land as well. The infected plants discovered on Long Island were 

 badly spotted and streaked, and on being examined micro- 

 scopically the cells were found to be filled with a tenuous 

 rhizomycelium, sporangia and spindle-shaped organs. Whether 

 or not the disease became sufficiently severe to have a pro- 

 nounced effect on the yield in uncertain, since the corn had not 

 yet reached the tassel stage at that time. 



The two species of Ligniera referred to were found in the 

 roots of Alisma plantago-aquatica and Isoetes lacustris from Van 

 Cortlandt Park, New York City and Culver Lake, New Jersey 

 respectively. Plasmodia and sporangesori in several stages of de- 

 velopment were very abundant in the roots, but no signs of 

 hypertrophy were evident. The genus Ligniera was established 

 by Maire and Tison (1909-1911) to include all species of the 

 Plasmodiophorales which fail to produce hypertrophy of the 

 host tissues, and in this respect the species which occur in 

 Alisma and Isoetes are to be classed in this group. While the 

 author doubts the validity of this genus, the generic name will 

 nonetheless be employed in the present paper. These two species 

 appear identical in size and development with L. alismatis and 

 L. isoetes described by Schwartz (1914) and Palm (1918) from 



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