352 bulletin: museum of comparative zoology. 



Number of bats examined. Number of parasites found. 



Lipoptena tolisina Speiser 

 Listropodia, sp. no v. 

 Penicillidia progressa Speiser 

 Nycteribosia amboinensis Rnd. 

 Ascodipteron speiserianum, sp. no v. 

 Raymondia pagodarum Speiser 

 Lipoptena tolisina Speiser 



Listropodia sp. no v. 

 Nycteribosia amboinensis Rnd. 



The Ascodipteron always occupied the same position in the host, 

 namely, under the skin at the base of the ear. Out of the seventeen 

 bats bearing this parasite, that I examined, one had three specimens, 

 two by one ear and one by the other, nine had two specimens and 

 seven only one specimen. 



I placed many bats, bearing these parasites, in cages but they 

 refused to eat any of the insects I supplied them with, and died within 

 forty-eight hours. In spite of this I was fortunate enough to procure 

 five pupae of Ascodipteron and three of P. progressa. 



Ascodipteron speiserianum, sp. nov. 



Stated briefly the life-history of this species is as follows : — The 

 imbedded female has the posterior portion of her abdomen protruding 

 from the host. A single egg passes from the ovarian tube into the 

 uterus, where it hatches in the usual pupiparous fashion, and the 

 larva, fed by the contents of the nutriment-glands, grows to maturity. 

 It is then ejected from the uterus and falls to the ground, where it 

 immediately forms a puparium and pupates. The adult fly emerges 

 in from thirty to thirty-three days and is then a perfectly normal insect, 

 with fully developed legs and wings. A hiatus now occurs in my 

 knowledge of the life-history, as I could not get the sexes to copulate 

 in captivity, but I anticipate that this takes place in a normal manner 

 whilst the female still has wings. The female then seeks her host, 

 and by the aid of the series of chitinous blades at the end of her 

 proboscis, cuts through the skin, she then gets rid of her legs beyond 

 the trochanter and her wings; her abdomen enlarges and engulfs 

 the thorax and head, so that eventually they lie at the bottom of a 

 pit, at the anterior end of the abdomen, as if they had become invagi- 



