BLOOD FEEDING HABITS OF ANOPHELINES 445 



horses, cattle and sheep, bordered the región studied in Concep- 

 ción. Nearly every house had one or more mongrel dogs ; 

 domestic goats were not uncommon. Upon a few occasions hens 

 were found sitting on eggs within dwellings ; it was not unusual to 

 find chickens running about in the human habitations. Some 

 places, e.g., houses no. 1, Rio Salí, and no. 355, Concepción, kept 

 hogs, but apparently the animáis were always shut up outside the 

 homes. 



Table 1 summarizes the data secured by the precipitin re- 

 actions. In spite of a careful selection of the more promising 

 specimens, nearly 11 per cent of those examined proved negativa. 

 Of the 581 positive specimens, 40, or 6.9 per cent, gave simul- 

 taneous reactions for two bloods. Although a couple of múltiple 

 reactions (i.e., for more than two bloods) were called negative for 

 statistical purposes, there seemed to be no good reason to doubt 

 an occasional combination. Henee, each blood concerned in a 

 combined reaction has been allowed half valué, and the total 

 percentages recalculated on this basis, as noted in the table. 



In the large series oí A. quadrimaculatus examined by King and 

 Bull (2), the ones taken from inside houses reacted as follows: 

 man, 38.4 per cent; horse, 20.1 per cent; cow, 18.6 per cent; pig, 

 7.7 per cent; dog, 10.0 per cent; cat, 2.6 per cent; chicken, 2.6 

 per cent. It will be seen that our figures are much higher for 

 man and dog, lower for horse, hog and cow (even if the results for 

 cow and sheep-goat are combined), and fairly comparable for cat 

 and chicken. Our percentages resemble somewhat those given 

 by King and Bull (2) for Killarney. 



These findings are readily explained by the exceeding domes- 

 ticity of A. pseudopunctipennis. This domesticity has been 

 previously emphasized by Petrocchi (3). Resting adults of this 

 species were rarely found outside of human dwellings. As a rule, 

 dogs sleep at night in the habitations of their masters; on the 

 other hand, cats commonly prowl around outside the houses at 

 night. This difference in habits, in conjunction with differences 

 in amoimt of exposed body surface, may well explain the di- 

 vergence in percentage of the two animáis attacked by A . pseudo- 

 punctipennis. 



