THE YELLOW FUNGUS. 27 



are usually more sunken than in A . Jiavo-citrina, and that its spores 

 are smaller. The orii!;inul description follows: 



Ascherfonia (lavo-citriiia P. Henn. StromatibuM carnosi.s, hypophyllis, sub- 

 disfoideo-imlvinatiH vel hcniis])hat'rico-d('i)rusHi.s, citrinis, 2-2.5 mm. diametor, 

 pruiiiosis, superue i)unctulato-i)ertusis, intus Hubaurauliis, mibiculo mcmbraiuiceo, 

 flavo; pycnidiis immersis oblongiy, paraphysibus filiformibuH, flexuoisis, hyaliniH, 

 140-180x1-1.5 micr., continuis; conidiis f usoideis, utrinque acutis, continuis, hyalinis, 

 12-18x2 micr.; conidiophonH brevibus, hyalinis, fasciculatis. 



The manner of development of the yellow Aschersonia upon the 

 larvae and puj^te is so like that already described for the red Ascher- 

 sonia that no further mention of it need be made here. 



The method of spore dissemination, so far as can be determined, 

 is also similar to that of the red fungus. 



BIOLOGY. 



The yellow Aschersonia, except when artificially introduced, has 

 never been found in groves infested only by the citrus white fly and so 

 far as observed thrives only on the cloudy-winged white fly. Dr. 

 Berger ^ re])orts having caused the infection of a few larvae of citri, 

 but states that tliis fungus did not increase in his experiments. The 

 same experience has been had by the authors at Bradentown, Fla. 

 It has been noted by the senior author attacking a scale insect on the 

 leaf of sweet gum (Liquidamhar styracijiua) at Winter Park, Fla. 



DISTRIBUTION. 



Up to* July, 1909, this fungus has been found growing naturally at 

 Altamonte Springs, Maitland, Mims, Oneco, Orlando, Oviedo, Wild- 

 wood, and Winter Park, Fla., and has been introduced into Bucking- 

 ham, Gainesville, Lakeland, Lake City, Largo, Lemon City, Manatee, 

 Miami, New Smyrna, Sutherland, St. Petersburg, and in the vicinity 

 of Turkey Lake in the western portion of Orange County, Fla. Its 

 occurrence in Brazil has already been noted. 



HYPERPARASITIC FUNGI. 



The yellow Aschersonia is subject to widespread parasitism by a 

 greenish-br<)^vn hyperparasitic fungus identified in March, 1907, by 

 Mrs. Patterson as Cladosporiuin sp. The attack of the latter upon 

 the yellow Aschersonia was first noticed by the senior author in the 

 summer of 1 906. During the winter of 1 906-7 it was estimated to have 

 overrun 95 per cent of the yellow pustules in certain groves at Winter 

 Park and Orlando, and has since been noted wherever the yellow 

 Aschersonia occurs. Tiie destruction of more than 90 per cent of 

 the supply of yellow Aschersonia spores during the fall and winter 

 must necessarily have a retarding influence on the spread of the 

 fungus at the })egiiining of the next season for its normal spread. 

 Frequent observations and experiments at both Winter Park and 



1 Bui. 97, Fla. Agr. Exp. Sta., p. 53. 



