PRESIDENTIAL ADDRESS. 13 



found to be dangerous in Italy and elsewhere viz. Anopheles 

 and Culex, but as yet the dangerous species have 

 not been found. For instance, Dr. Robert Dick, Medi- 

 cal Health Officer at Newcastle, tells me that Ano- 

 pheles annulipes (Walker), extends from Newcastle 25 

 miles inland to the Maitland district, and that about 

 Maitland also Stegomyla notoscrlpta (Skuse) is very 

 common. Anopheles, as I have said, is the malaria carrier. 

 A Stegomyla carries yellow fever. 



As a local example of at once the tropical disease and its 

 carrier, Dr. Dick tells me of a case of Filariasis in a boy 

 born in that district, and who has resided only there and for 

 a time in Queensland. In the blood of this boy Filar ia 

 nocturna is present and he has most distressing symptoms. 

 Dr. Dick on several occasions hatched out the eggs of 

 Culex fatigans, these mosquitoes fed on the boy and acted 

 as efficient hosts, and since transformed filarial were pre- 

 sent in the labium of the mosquitoes twenty days after the 

 feeding, they could doubtless have transferred them to any 

 other boy to which they directed their attention, for the 

 insects that do these things are all females. Dr. Thomas 

 Bancroft of Brisbane who has done a great deal of splendid 

 work in this field has shown that Culex ciliaris also can 

 convey the fllaria from the diseased to the healthy. 



One of the most striking places to come under treatment 

 quite recently is the Isthmus of Panama, where the great 

 interoceanic canal is in course of construction. There in 

 the canal zone yellow fever has been eliminated, malaria 

 enormously reduced and the country made almost into a 

 health resort, if we can believe many accounts. One, 

 visitor saw one harmless mosquito and heard the singing 

 of two others — why not two singings of one? — in six days. 

 Six thousand Americans living there lost one of their 

 number by death in three months. In New York 30 from 



