Feb. '08] JOURNAL OF ECONOMIC ENTOMOLOGY 71 



Africa, was at first (1903) thought by Lounsbury to be transmitted 

 by the Brown Tick, Rhipicephalus appendiculatus, alone, but further 

 investigation has proven that four other species of the genus, simus, 

 evertsi, nitens and capensis may also transmit it. The Brown Tick 

 imbibes the infection as a larva or nymph and transmits it in the 

 following stage of the same generation. In the adult stage both sexes 

 transmit the disease, but one or two specimens being necessary. The 

 infection does not pass through the egg. 



Dr. Arnold Theiler," Government Bacteriologist of the Transvaal, 

 has found biliary fever or piroplasmosis of horses, mules and donkeys 

 to be transmitted by the Red-legged tick, Rhipicephalus evertsi, one 

 of the species found by Lounsbury to transmit African coast fever. 

 The infection is imbibed as a nymph and transmitted by the adult. 

 Doctor Theiler^^ also seems to have shown that spirillosis of cattle in 

 South Africa is transmitted by Margaropus decoloratus. Koch has 

 since found cases of this spirillosis in Daressalem, German East Af- 

 rica, and has succeeded in tracing the spiroehaetae to within the eggs 

 of the ticks. 



To Doctors Marchoux and Salimbeni^® belongs the credit of first 

 demonstrating that a tick transmits a spirochaetag. In 1903 they pub- 

 lished a report of their studies, showing that the Fowl Tick, Argas 

 miniatus, is an agent in the transmission of spirillosis in fowls at Rio 

 Janeiro, Brazil. The disease seems to be transmissible by the innocu- 

 lation of infectious blood. While the tick is one agent, the disease 

 may also be transmitted by feeding blood or excrement of diseased 

 fowls, thus it does not seem that the spiroehaetae is necessarily depend- 

 ent biologically upon the tick. Balfour^'^ has found what appears 

 to be the same disease of fowls in the Soudan of Africa, and Reaney^* 

 that it is endemic in Central India. 



Motas^^ has shown that Rhipicephalus hursa transmits carceag or 

 ovine piroplasmosis in Europe. This tick passes the larval and nym- 

 phal stages upon the same animal, but drops to the ground for the 

 second molt. The infection (as is the case of Haemaphysalis leachi) 

 is transmitted by the adult, when the adult of the previous generation 

 has fed upon an infectious host, and not by the larva or nymph. 



KosseP° and associated investigators have demonstrated that piro- 

 plasmosis of cattle in Europe is transmitted by Ixodes ricinus. This 

 tick drops for both molts, the larva and nymph being pathogenic. 

 This is of importance, as it may be found to do the same in this 

 country. 



In 1905 Dutton and Todd^° published an account of their study of 

 the so-called human tick fever in Congo Free State. They found 

 it to be produced by a spirochaetas that has since been determined by 



