( 267 ) 
Notes as to the Pathogenicity of certain Mosquitoes with 
respect to Filaria Nocturna and Malignant 
Tertian Malaria. 
By G. F. Leicester, m.b., ch. edin. 
Experiments by direct feeding on patients with Filaria Nocturna and 
Malaria Parasites of the Malignant and Benign tertian type. 
Filaria Nocturna. 
With regard to filaria it was found that embryos enter the thoracic 
muscles of the mosquito and undergo further development m the following 
mosquitoes (exclusive of Culex Fatigans and Mansonia Uniformis). 
Anophelina :— 
Myzovhyncus Sinensis 8 fed 5 infected. 
,, Barbivostas 5 fed 4 infected. 
,, Peditcuniatus 1 fed 1 infected. 
Culicina:— 
Stegomyia Gracilis 8 fed 6 infected. 
,, Perplex a 3 fed 3 infected. 
Scutomyia Albolineata 3 fed 2 infected. 
Culex Gelidus 2 fed both infected. 
,, Sitiens 8 fed 1 infected. 
,, Nigvicephala 1 fed none infected. 
„ Uniformis 3 fed 5 infected. 
F ctniovhyncus Domesticus 1 fed 1 infected. 
Mansonia Annulipes 6 fed 6 infected. 
The case of filaria was a good one and the same was used throughout. 
The mosquitoes were kept" in test tubes and at the ordinary room 
temperature here averaging about 85° Fahr. The dissections were, made 
in all cases on mosquitoes about to die and were killed immediately before 
dissection. The rate of development was very varied in different species 
but singularly uniform in different members of the same species. The 
development in Culex Fatigans was taken as the standard and the develop¬ 
ment of the worms was compared with that in Culex Fatigans under simi ar 
conditions. Development in Mansonia Annulipes was remarkably slow and 
may be said to have been three or four days late, i.e., a mosquito dissected 
four days after feeding might shew worms no further developed than they 
would have been in Culex Fatigans atone or two days. On the other 
hand in Myzovhyncus Sinensis the development was more rapid than in any 
other mosquito dissected not excepting Culex Fatigans. 
