180 The Philippine Journal of Science 1919 
dangerous plague flea {Lsemopsylla cheopis Rothsch,) prefers to 
live. That the plague flea does not confine itself to this host, 
the terrible outbreaks of human plague in this and other coun- 
tries too well have testified, since it is the only known medium 
for the transmission of this deadly malady from the rat to man. 
The so-called human flea {Pulex irritans L.) is rarely met 
with in the Philippines, and as specimens have been taken only 
in Manila and Iloilo it is presumed that they are brought here 
by steamers. 
It will be seen that all the insects discussed in this section, 
including flies and fleas, are semiobligatory parasites that in 
the adult stage require the blood of vertebrates but live apart 
from the host as larvse. 
Another interesting insect is the red-banded cone-nose (Cono- 
rhinus rubrofasciatus de Geer), which has been recorded from 
the Oriental Region, Africa, and America, and is closely related 
to insects of similar habit in the United States and Brazil. 
One of its common nam.es in* the United States is bedbug hunter, 
as it is known to suck the blood which these pests have taken 
from the human host. From this habit has naturally resulted 
the taking of blood directly from the sleeping host, and at least 
one case is known of a student in Manila who was bitten by 
these insects. In June, 1914, an adult and a half-grown larva 
were sent to my office by the Director of Health ; the specmens 
were full of human blood, and one had been crushed by the 
person bitten. 
It is stated by Herrick that a person bitten by the American 
species (Conorhinus sanguisugus Le Conte) did not recover for 
more than a year. 
These insects are so large and conspicuous, measuring from 
18 to 20 millimeters in length, that it is strange they are not 
reported more frequently; but they escape detection undoubtedly 
because they are very quick fliers and are nocturnal in their 
habits. They cannot of course penetrate a well-kept mosquito 
net, but could easily crawl under one that is torn or carelessly 
adjusted. 
A close relative in Brazil (Conorhinus megistus Burm.) is the 
transmitter of a deadly human trypanosome {Schizotrypanum 
cruzi Chagas) ; an admirable account of its life history and 
habits has been given by Neiva.^® The Philippine species should 
be looked upon with suspicion so far as disease transmission 
“Household Insects. New York (1914), 422. 
” Mem. do Inst. Osw. Cruz (1909), 1, 159-218, 4 pis. 
” In Chagas, loc. cit. 
