444 Agricultural Experiment Station, Ithaca, N. Y. 



not occur until the disease has become well advanced. The pupae 

 sometimes move spasmodically when irritated, even after the color 

 has spread all over the pads and to some adjacent parts of the 

 thorax. After the death of the insect, the mycelium appears as a 

 close felt spreading over the entire ♦surface of the body. All the 

 specimens in the check cages remained unaffected and well through- 

 out, all of Them emerging as adults. A dilution culture proved the 

 fungus to be the same as that originally used for infection. 



On August 18, 1894, about forty Harlequin Milkweed cater- 

 pillars, Cycnia egle, were dusted with eonidia of the fungus. After 

 five weeks no effects were visible. The caterpillars grew and 

 eventuahy pupated. The pupse did not exhibit any traces of the 

 fungus. 



Two large cages of our common Fall Webb-worm Ilyplantria 

 cutiea, were dusted with eonidia obtained from a potato culture. 

 After five weeks no results were visible. Eventually they nearly 

 all pupated, presenting no traces of the fungus. 



On August 22, 18. '4, thirty caterpillars of the Eed-humped Apple- 

 worm, Oedeonasia concinna, were dusted with eonidia obtained 

 from a potato culture. After about a month, eight caterpillars and 

 two pupte were found to be dead and completely covered with a 

 characteristic felt which exhibited the ordinary mode of growth 

 and fruiting. 



A cage containing caterpillars of Melitea phaeton stood near the 

 cage of infected cabbage-worms, and three of these became acci 

 dentally infested and died, producing the characteristic growth. 



The cages used in the experiments described, were ordinary glass 

 cylinders closed at the upper end with muslin. The air in them 

 was slightly, if at all, more humid than that outside. 



A culture tube, in which Mr. Pieters was growing a pyrenomy 

 cetous fungus, was left open for a short time and a number of our 

 small red ants, troublesome in the laboratory, entered, probably 

 bringing the eonidia of this fungus with them on their bodies. 

 The cotton plug of the culture-tube was reinserted and the ants left 

 to their fate. They died in about a week and in due time, became 

 covered with a white growth of the fungus, the conditions l^eing 

 favorable to its development. The growth was in this case loose 

 and fluffy. A dilution culture and pure cultures, in flasks of potato, 

 proved it to be the species in question. 



