404 PROCEEDINGS OF THE ACADEMY OF [^May, 



The atteutiou of the writer was drawn to the swellings a year or 

 two ago, while botanizing in the coastal i^lain of New Jersey. 

 Si>ecimeus of the swellings caused by the two fungi were collected 

 in a cedar swamp at Island Heights Junction, N. J. Both the 

 fanlike growth of the younger branches and the larger knotty 

 growths on the older branches and the trunk of the trees Avere met 

 with in this cedar swamp. The large knob-like swellings, a foot or 

 more in diameter, girdling the trunk of large trees, were seen in a 

 cedar sw^amp at Newfield, IST. J, 



Methods. 



Sections of the swellings caused by Gyvmosporangium biseptatum 

 were made by means of a plane. The smaller sections w'ere 

 mounted in the usual way on slides, and the larger sections were 

 mounted on window glass with thinner pieces of white glass as 

 covers, and these preparations Avere then placed over a steam radia- 

 tor until the balsam was perfectly dry and hard. The covers were 

 kept in place during the drying by spring-clip clothes pins, which 

 suited the purpose admirably. Bismarck-brown, aniline-green and 

 an admixture of acid-fuchsin and methyl-green Avere used with 

 satisfactory results in the demarcation of the tissues. 



Appearance of the Savellings. 



The SAvellings produced by Gymnosporangium biseptatum Ellis are 

 quite characteristic. The disease may appear on trees Avhich are 

 from fiA'e to six feet high, Avith stem about an inch in diameter. 

 In these young trees the sAvelliug surrounds the Avhole stem, being 

 about three inches long and approximately spindle-shaped (Pis. 

 XXII, XXIII, figs. 1, 2, 3, 4, 5). The bark is deeply fissured 

 by longitudinal cracks, Avhicli are also someAvhat wrinkled at the 

 bottom (fig. 3). In a stem three-eighths inch diameter, the AA'ood 

 inA'oh^ed is quite sound, although in dried specimens of a more 

 decided yellow color than the Avood of the stem below, Avhich is 

 AA'hitish in color. As the mycelium of the fungus is perennial, these 

 club-shaped enlargements keep constantly increasing in length and 

 diameter from year to year. In another someAvhat larger specimen 

 studied, the burl reaches a diameter of an inch and a half and is 

 about six inches long. The fissures become much deeper, due to 



