24 



BULLETIN 597, U. S. DEPARTMENT OF AGRICULTURE. 



Table VI. — Fungus development upon pupce of Gastrophilus haemorrlioidalU 

 in new tin boxes at Aberdeen, S. Dak,, 1915-16. 



Larvee 



from 



rectum. 



Collection and environment. 



o 



© 

 ft 



"3 

 P< 



ft 



© 



03 

 & 



K 



M 



B 



T3 



_o 



OS 



p. 

 ft 



T3 



© 

 © 



1 



S3 



> 



u 



C3 



h3 



© 

 & 



P 

 Si 

 > 

 u 

 e3 

 1-3 



Number 

 infected. 



Adults 

 emerged 



Temperature 

 collection to 

 emergence. 



S3 

 p 



P4 



si 

 > 





©" 



a 



© 



2 



.a 



i 

 1 



1915. 

 June 11' 



From perspiring horses 



Hours. 

 79-220 



20-219 



6-25 



23 



6-43 



5-18 



21-29 



22-32 



20-39 

 77-102 

 48-72 

 22-70 

 4-122 

 19-166 

 22-190 

 3-6* 

 21-67 

 21-31 



1915. 

 June 15 

 June 30 

 June 25 

 July 13 



Days. 

 34-36 

 35-38 

 30-32 

 34 



13 

 10 

 34 



5 



1 



3 



40 



4 



7 

 13 

 2 



8 

 10 

 62 

 20 

 15 



4 

 14 

 19 



10 



10 



29 



3 



1 



3 



40 



4 



7 

 11 



2 



7 

 10 

 59 

 17 

 13 



4 

 12 

 18 



10 

 10 

 29 



3 

 

 3 

 40 

 4 



7 



11 



2 



7 



10 



59 



16 



12 



4 



2 



18 



3 



5 



2 

 5 



7 

 1 



2 

 1 



6 



88 

 88 

 85 

 85 



°F. 

 40 

 40 

 41 

 41 



°F. 

 65.54 

 64 66 



June 21 





63 88 



July 6 

 Do... 



With fresh horse manure . . 

 From perspiring horse 



63.85 





July 13 



...do 



July 16 



1916. 

 May 29 

 June 14 

 June 22 

 June 12 

 June 17 

 June 29 

 July 1 

 July 3 

 July 6 

 July 25 

 July 28 



33-36 

 33-36 

 33-35 



"21-25" 



21-29' 



20 





1 



14 

 1 



1 

 11 



1 



85 

 85 

 85 



41 

 41 

 41 



62 12 



July 10 



With moist loam 



64.32 



July 13 



1916. 

 May 17 2 





64.43 



On blotting paper 





June 2 2 

















June 5 











7fi 



42 



59.14 



Do.2.. 



With moist sand 









June 9 2 



do 













June 24 



do 





24 



15 



96 



48 



74.67 



June 26 2 







June 27 







4 



6 

 1 



96 

 96 



56 

 58 



75.73 



July 1 



With moist sand 



77.07 



July 18 2 









July 24 





5 



3 



98 



51 



70.19 









1 Determined by Mrs. Flora W. Patterson as Sporotrichum minutum. 



2 Determined by Dr. A. T. Speare. 



Except the collection on May 17, 1916, larvae vrere not washed. 



Several lots were sent to Dr. A. T. Speare, Mycoentomologist of 

 the Bureau of Entomology, who made cultures and determined the 

 characters showing that all the infestations were of one species and 

 were not Sporotrichum. 



According to Dr. Speare about 50 per cent of the pupae sent to him 

 produced adults. He reported that the fungus seemed to be restricted 

 in its development to the chitinous wall of the puparium, and that 

 death, if caused by the fungus, must have been brought about in some 

 unusual way, as, for example, by closing the spiracles. However, 

 the fungus seems to develop best at the rings of the segments and is 

 seldom observed upon the posterior spiracles. 



In Table IV it will be observed that a fungus appeared upon pupse 

 which had been subjected to heat tests, and this was apparently the 

 same as has been observed in other experiments. A comparison of 

 results and mortalities due to the fungi indicates that there is little 

 hope of controlling the Gastrophilus by encouraging natural develop- 

 ment of the fungus. Eighteen lots containing 283 larvae produced 259 

 pupae, of which 247 became infected with fungus in rearing experi- 

 ments. Twelve of the lots, containing 194 pupae, were retained for 

 observations on mortality. Of these, 64 males and 47 females 

 emerged as normal adults, giving 57 per cent emergence. The adults 



