i iS Mosquitoes 



sachusetts, describes the finding of gregarines in A. 

 maculipennis. They were on the outer surface of 

 the stomach, on the Malpighian tubes, and in the 

 salivary glands. They resemble malarial oocysts in 

 appearance. 



Filariasis. — Filaria, the cause in the Orient of ele- 

 phantiasis, is by no means unknown in this country. 

 There is one case of several years' standing in Wash- 

 ington, D. C. In this individual, a drop of his blood, 

 taken after 8 or 9 P. M., will show several active worm- 

 like embryos. During the day, as is always the case 

 with this disease, the embryos retire to the capillaries 

 of the lungs. The adult Filaria lives in the lym- 

 phatics, especially in the glands. Here the female 

 gives birth to a vast number of capsulated embryos, 

 which often choke up the lymph vessels. The result 

 is that the connective areolar tissues fill up with 

 lymph and the parts swell to enormous size. The 

 embryos swim about in the lymph and thence make 

 their way into the blood. Dr. Manson, connecting 

 the nocturnal appearance of the parasites in the peri- 

 pheral circulation with the night-feeding habits of 

 mosquitoes, began a series of observations which 

 proved his suspicion to be true. The intermediary 

 host in this case is apparently not confined to a single 

 genus, but several species of both Citlex and Anopheles 

 may carry the parasite, which is somewhat unusual. 

 The embryos lose their capsules and work through 

 the stomach wall of the mosquito into the thoracic 

 muscles, where, for a period of from fourteen to 

 twenty days, they remain quiescent, growing and 

 developing into larvae. They then become active 



