62 HATCH EXPERIMENT STATION. [Jan. 



cences contain masses of the l)rigbt orange-yellow colored 

 spores of the fungus which causes the disease. The fungus 

 has a peculiar course of development. It not only exists in 

 the form seen upon the quince, but has also another form or 

 stage, living upon a different kind of plant and quite differ- 

 ent in appearance. This stage of the fungus lives upon the 

 red and white cedar and the juniper, and is one of the forms 

 which produce upon those plants the abnormal growths pop- 

 ularly known as "cedar apples." These cedar apples are 

 peculiar outgrowths upon the twigs of cedars and junipers, 

 reaching their complete development in early spring. They 

 are oftentimes regarded as the proper product of the tree, or 

 as insect galls, — which ideas are equally incorrect. These 

 growths begin to form in midsummer, developing as small 

 excrescences upon the twigs and gradually increasing in 

 size until winter, w^hen they are nearly full grown. An 

 "apple" consists at this stage of an abnormal mass of the 

 cells of the tree, with the filaments of the fungus growing 

 abundantly between them. Remaining thus over winter, 

 the first warm, moist weather of spring starts it into further 

 growth and development. Upon the surface of the aflected 

 wood numerous projections appear, of a conical shape, and 

 composed of a yellow, gelatinous substance. These projec- 

 tions are composed of a mass of the fungous filaments and a 

 gelatinous substance which they secrete. In them are pro- 

 duced the spores of this, the teleuto stage. These spores 

 are composed of two cells and borne on long stalks. The 

 sudden appearance of these peculiar growths on cedar trees 

 just after a spring rain is often taken for the blossoming of 

 the tree, but is in reality the fructification of the fungus 

 parasitic upon it. The gelatinous appendages of the cedar 

 "apples" soon dry up and wither away after the rain, but 

 not until the teleuto spores contained in them have ger- 

 minated and produced secondary reproductive bodies called 

 sporidia. These are carried away in the air, and proceed 

 to infect, not cedar trees, but quinces or one or two other 

 related plants. Upon the surface of these they germinate 

 and produce filaments which grow into the substance of the 

 young fruit or stems, and by their presence there cause the 



