130 GYPSY AND BROWN-TAIL MOTHS. [Jan. 



and is given by Saccardo as Penicillium brevicaule, Sacc. 1 The 

 fungus is probably a harmless one, and its occurrence on the dead 

 caterpillars and pupse was probably incidental and of secondary 

 importance. 



Another species of fungus was always present on the diseased 

 and dead pupae and caterpillars, which proved to be a form of the 

 Eutomophthoreae, which includes a class of fungi represented by 

 about half a dozen genera, and largely confined to insects. We 

 did not attempt to secure cultures of this, but were able to examine 

 the same in connection with the dead pupae, etc. 



This fungus proved to be Empusa aulicce, Reichardt, as given 

 by Saccardo, 2 or Empusa grylli in Thaxter's Monograph. 3 This 

 species is parasitic on certain insects, and occurs in Europe and 

 the United States. Thaxter records numerous epidemics among 

 grasshoppers resulting from this fungus, and it occurs also on 

 rnoth larvae and caterpillars. 



In addition to the above fungi, we found in some of our material, 

 taken from the body cavities of the brown-tail pupae, colonies of 

 bacteria which were quite general and uniform, and appeared of a 

 pure type. These colonies were so uniform and appeared so con- 

 stantly that they were isolated and cultured in the usual manner; 

 but no attempt was made to establish the identity of the organism 

 with any described forms, since there was no opportunity for 

 ascertaining whether it possessed any pathogenic value in this 

 particular case. 



After isolating the bacterial cultures in an absolutely pure form, 

 some experiments were undertaken in the parasitic laboratory in 

 Maiden by Orton L. Clark, under Superintendent Kirklaud's super- 

 vision. It was, however, getting late in the season for experiments 

 with the brown-tail pupae, since the moths were rapidly emerging. 

 An outline of these experiments follows, together with the results 

 obtained : 



EXPERIMENTS WITH FUNGOUS DISEASES. 



Experiment I. (a) Ten diseased pupa? were placed in a glass jar 



with 10 normal pupae. Result: 3 normal 

 pupae became diseased. 



(b) One diseased pupa was put in a glass with 10 

 normal pupae. Result: no change. 



1 Sylloge Fungorurn, Vol. IV., p. 84. 



2 Loc. cit., Vol. VII., p. 282. 



3 Entomophthorea' of the United States, in Memoirs of Boston Society of 

 Natural History, Vol. IV., pp. 1-59, 1886-93. 



