ABSTRACTS. 30/ 



was found infesting the berries, which when bred proved to be 

 Rhagoletis pomonella Walsh, the apple maggot or railroad 

 worm (Journal of Economic Entomolog}^. 1914, Vol. VII, pp. 

 398-399). There were also obtained from larvae of this species 

 collected at Cherryfield, Maine, in August and September, 1913, 

 twenty-one specimens of a parasite, which emerged from pu- 

 paria kept under laboratory conditions, at various dates between 

 February 25 and April 21, 19 14. 



No parasite has been recorded from Rhagoletis pomonella 

 Walsh, previous to this time. 



The species belongs to the family Bracmiidae and to the 

 subfamily Opiinae. In this same group are placed many of the 

 parasites, including one of this genus, which are recorded by 

 Silvestri as bred from various fruit-flies (Bulletin 3, Hawaii 

 Board of Agrculture and Forestry, 1914.) 



Specimens of this species were swept on the blueberry bar- 

 rens of Washington County last summer, where apparently they 

 had considerably reduced the number of the maggots as com- 

 pared with the preceding season. Specimens of the CherryfieM 

 parasites were submitted to Mr. E. A. Richmond, of Cornell 

 University, who determined it as a new species. 



EFFECT OF TEMPERATURE ON GERMINATION 

 AND GROWTH OF THE COMMON POTATO-SCAB 

 ORGANISM.* 



The object of this study was to determine as closely as pos- 

 sible the optimum, maximum and minimum temperatures for 

 the growth of the common potato scab organism in artificial 

 cultures, also the effects of variations in temperature upon the 

 germination of the so-called "gonidia" which it produces in i\\& 

 fruiting stage upon such cultures. The organism under consid- 

 eration is what has been known since 1892 as Oospora scabies 

 Thaxter and which Lutman and Cunningham have recently 



*This is an abstract of a paper with the same title by Michael Sha- 

 povalov published in the Journal of Agricultural Research, Vol. IV, No. 

 2, pp. 129-134. May 15, 1915. 



