THE BEDBUG AND OTHER BLOODSUCKING BUGS 399 



louse. Nuttall in 1907 experimented with the Russian strain of this 

 disease and succeeded in transmitting relapsing fever, in one expferiment, 

 to a mouse by the bite of Cimex lecttdarius. He found that usually the 

 spirochaetes were digested by the bugs, the time depending upon the tem- 

 perature. Miigge, in 1897, infected monkeys with the contents of bugs, 

 removed twenty-four hours after they had fed on relapsing fever blood. 

 Karlinski and also Schaudinn observed the survival of spirochaetes in 

 two bugs for 30 days or more. Various authors have failed to transmit 

 spirochaetes by bugs, but it is -probable that these failures were because 

 they attempted to transmit by means of the bite, rather than by crushing 

 or scratching in the contents of a bug or its feces. Tictin, however, 

 while suggesting that the bedbugs might transmit the disease by their 

 bite, also suggested that it might be by their being crushed and the 

 contents entering the skin through excoriations due to scratching.- 



In summary we may draw the conclusion that probably all disease 

 organisms which are capable of passing part of their cycle in the bed- 

 bug will be found to be transmitted through the scratching in of the 

 feces of the bug, or by the rupturing of a bug while in the act of feeding, 

 or over an excoriation of the skin. It is quite possible that any organism 

 which the bug may take up from the blood and which in like manner 

 is infective to the blood can be transmitted under favorable conditions in 

 this manner. 



There is most certainly a very promising field for research in the 

 working out of the possibilities of disease transmission by blood-sucking 

 bugs. 



LIFE HISTORY NOTES 



This lecture deals primarily with the bedbugs of the genus Cimex, 

 family Cimicidae, but also contains mention of the false bedbugs, or 

 kissing bugs of the genus Triatoma (Conorhinus) , family Reduviidae. 



The best discussion in English, with illustrations, of the genus 

 Triatoma (Conorhinus) is given by Patton and Cragg. These bugs live 

 on human and mammalian blood. The egg of Triatoma tuhrofasciata 

 (De Geer) of India is rounded at one end and flattened at the other, 

 which forms a kind of operculum. It measures 2 mm. by 1 mm. The 

 incubation period varies from 20 to 30 days. The development is similar 

 to that of all winged Reduviids, each stage showing more developed wing 

 pads, until the fully winged adult stage is reached. The development 

 requires several months from eggs to adult. 



Triatoma megista (Burmeister) of South America is almost entirely a 

 domestic insect. The adults enter inhabited houses, but never those which 

 have been abandoned. In old houses they are to be found in cracks and 



