. Bulletin of the Department of Agriculture. Agriculture. 12 BULLETIN 810, U. S. DEPARTMENT OF AGRICULTURE. seems quite probable that the disease might in some cases be carried over for months or even over winter through the medium of these rubberlike scales. It is of interest to know that the amount of disease resulting imme- diately from inoculations in which scale material is used is much less than when larvae recently dead of the disease are used. This is true also of dead larvse stored in Petri dishes compared with smears allowed to dry immediately from larvae recently dead of the di
. Bulletin of the Department of Agriculture. Agriculture. 12 BULLETIN 810, U. S. DEPARTMENT OF AGRICULTURE. seems quite probable that the disease might in some cases be carried over for months or even over winter through the medium of these rubberlike scales. It is of interest to know that the amount of disease resulting imme- diately from inoculations in which scale material is used is much less than when larvae recently dead of the disease are used. This is true also of dead larvse stored in Petri dishes compared with smears allowed to dry immediately from larvae recently dead of the disease. These facts indicate a possible deleterious effect on Bacillus pluton of the sec- ondary invaders multiplying in the decaying larvae. STKEPTOCOCCUvS APIS It is most probable that Streptococcus apis is the species that was isolated from diseased brood by Burri (3) and referred to by him in 1906 as "giintheri-forms.''^ Maas- sen described it in 1908 (8). The organism grows well at incubator, room, and refrigerator tempera- tures in most of the media ordi- narily used in the laboratory. Its cultural characteristics suggest the micrococci rather than the streptococci. Confusion in some of the earlier investigations was due evidently to the resemblance of Streptococcus apis and Bacillus pluton morphologically. To this FIG. apis. fact is duc the chief interest in the species Streptococcus apis. Wlien encountered in larvae dead of European foulbrood it can be identified readily by culturing. The generic position of this species should be considered as being not altogether certain. Occtirrence.—Streptococcus api^ is occasionally encountered in larvse dead oE European foulbrood and often is present in larse numbers. Morpholoyy.—It is more or less spherical (fig. 3; PI. VII, E), occurring singly and in pairs with occasionally a chain of 2 or more pairs when grown in liquid media. In larval remains not infrequently the ends may be somewhat pointed. Stainin
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