133 



by McCoy and Mitzmain they report never having seen this ejection 

 of rectal contents taking place. It might also be stated that where 

 they used plague-infected fleas none of the animals developed plague 

 after being bitten. 



ENUMERATION OF FLEAS THAT HAVE BEEN FOUND ON RATS. 



Various writers have reported the following fleas taken off rats: 



Family SARCOPSYLLID^ Taschenberg. 



Genus DERMATOPHILUS. 



1. Dermatophilus c&cata Enderlein. Seventeen specimens (fe- 

 males) were found by Doctor Enderlein on the skin behind the ears 

 of a specimen of Mus rattus from Saopaulo, Brazil. 



Genus ECHIDNOPHAGA Olliff. 



2. Echidnophaga gallinacea West wood. Tiraboschi has found this 

 flea on the Mus rattus in Italy. 



3. Echidnophaga rhynchopsylla Tiraboschi. This flea has been 

 taken in Italy from Mus rattus and Mus alexandrinus. It has been 

 described by Rothschild under the name of Echidnophaga murina. 



Family PULICID^ Taschenberg. 

 Genus CERATOPHYLLUS Curtis. 



4. Ceratopyhllus fasciatus Bosc. This is the common rat flea of 

 Europe and the United States. It has also been found in Cape 

 Town, Australia, and is occasionally found on rats in India. 



5. Ceratophyllus londiniensis Rothschild. This flea has been taken 

 off mice in England; off rats in Italy (Ceratophyllus italicus Tira- 

 boschi) and has been found once on Mus rattus in San Francisco, 

 Cal. 



6. Ceratophyllus acutus Baker. This is the common flea of the 

 California ground squirrel; and has been taken off Mus norvegicus in 

 San Francisco, Cal. 



7. Ceratophyllus anisUs Rothschild. This flea has been described 

 by Rothschild from Yokohama, Japan, taken off Felis sp. One 

 specimen was found in San Francisco, Cal., taken off Mus norvegicus. 



8. Ceratophyllus niger Fox. This flea is commonly found in San 

 Francisco, Cal., in chicken yards and sparrows' nests and has also 

 been found on rats, Mus norvegicus, and on man. 



9. Ceratophyllus consimilis Wagner. 



10. Ceratophyllus lagomys Wagner. 



11. Ceratophyllus mustelde Wagner. 



12. Ceratophyllus penicilliger Grube. 



These fleas have been taken off Mus norvegicus in Europe. 



