July 1. 1911 



405 



feeding and has begun pupation. At tliis 

 time it is sealed over in the comb (Fig. 2, o, 

 b,f). The first indication of the infection 

 is a sHght brownish discoloration and the 

 loss of the well-rounded ajipearance of the 

 normal larva (Fig. 2, I) . At this stage the 



ly removed by the bees; but when they are 

 left they usually become sunken (F'ig. 2, g, 

 c,j) and frequently perforated (Fig. 2, c,J). 

 As the healthy brood emerges the comb 

 shows the scattered sunken cappings cover- 

 ing dead larvip (Fig. 4), giving it a charac- 

 teristic appearance. 



Pu]jct^ also niay 

 die of this disease, in 

 which case they, too, 

 dry down (Fig. 2, o, 

 d), become ropy, and 

 have the character- 

 istic odor and color. 

 The tongue frequent- 

 ly adheres to the up- 

 \^er side wall and 

 often remains there 

 even after the ]iupa 

 has dried down to a 



Fig. 2. — American foul brood: o, h, f, normal sealed cells; c. J. .sunken cappings, showing perforations' 

 fir, sunken capping not perforated: h. I. m. ii. cj, r, larva- affected by disease; e. i, p, .s. scales formed from 

 dried-down larvae; </. o, pupae affected by disease. Three times natural size, (original.) 



disease is not usually recognized by the bee- 

 keeper. The larva gradually sinks down in 

 the cell and becomes darker in color (Fig. 2, 

 h, m), and the jjosterior end lies against the 

 bottom of the cell. Frequently the segmen- 

 tation of the larva is clearly marked. By 

 the time it has jjartially dried down and has 

 become quite dark brown (coffee-colored) 

 the most typical characteristic of this dis- 

 ease manifests itself. If a match-stick or 

 tooth-pick is inserted into the decaying mass 

 and withdrawn the larval remains adhere to 

 it and are drawn out in a thread (Fig. 3), 

 which sometimes extends for several inches 

 before breaking. This rojjiness is the chief 

 characteristic used by the bee-keeper in di- 

 agnosing this disease. The larva continues 

 to dry down and gradually loses its roi)iness 

 until it finally becomes merely a scale on 

 the lower side wall and base of 

 the cell (Fig. 2, e, ^j, s) . The 

 scale formed by the dried-down 

 larva adheres tightly to the cell 

 and can be removed with diffi- 

 culty from the cell wall. The 

 scales can best be observed when 

 the comb is held with the to}) 

 inclined toward the observer so 

 that a bright light strikes the 

 lower side wall (Fig. 4). A very 

 characteristic and usually pene- 

 trating odor is often noticeable 

 in the decaying larvae. This can 

 perhaps best be likened to the odor of heat- 

 ed glue. 



The majority of the larvse which die of 

 this disease are attacked after being sealed 

 in the cells. The cappings are often entire- 



scale. Younger unsealed larvse are some- 

 times affected. Usually the disease attacks 

 only worker brood, but occasional cases are 

 found in which queen and drone brood are 

 diseased. It is not certain that race of bees, 

 season, or climate has any effect on the vir- 

 ulence of this disease, except that in warm- 

 er climates, where the breeding season is 

 prolonged, the rapidity of devastation is 

 more marked, 



EUROPEAN I<X)rJL BROOD. 



European foul brood was formerly called 

 "black brood" or "New York bee disea.se." 

 The name "black brood" was a poor one, 

 for the color of the dead brood is rarely black 

 or even very dark brown. f]uropean foul 

 brood usually attacks the larva at an earlier 

 stage of its development than American foul 

 brood, and while it is still curled up at the 



Fig. 3. — The ropiness of American foul brood. (Original.) 



base of the cell (Fig. 5, ?•). A small percent- 

 age of larvae dies after capping, but some- 

 times quite young larvae are attacked (F"ig. 

 5, e, m). Sunken and perforated cappings 

 are sometimes observed just as in American 



