640 



NEMA THELMINTHES 



with a bulbous cuticular expansion at the tip of the tail. Anus 

 0-25 millimetre in front of the posterior extremity, vulva 0-71 milli- 

 metre behind the anterior end. 



Life-History. — ^The egg develops into a microfilaria which has 

 no sheath, shows no periodicity, and measures 200 by 5 Its 

 tail is tapering and sharp pointed, and it moves actively. Nothing 

 further is known as to the life-history. 



Pathogenicity —Nil . 



Filaria inermis Grassi. 



Synonyms. — (?) Hamularia lymphatica Treutler; (?) Filaria 

 palpebralis Pace, 1867; (?) Filaria labialis, etc. 



Several female filaria worms have been described from Southern 

 Europe as occurring in subcutaneous swellings in various parts of 

 the body in man and horses. These resemble the forms recorded by 

 Addario and Alessandrini under the name Filaria conjunctivce, but 

 differ, however, in the position of the vulva. 



(Microfilaria) Le Dantec, 1904. 



A collective group of the larvae of unknown adult Filariidse found 

 in the blood of man and other vertebrates. 



(Microfilaria) powelli Penel, 1905. 



This microfilaria was found by Powell in 1903 in the blood of a 

 Bombay policeman. 



It showed a nocturnal periodicity (?), was provided with a sheath, 

 measured 131 by 5-3 ^, and had a truncated tail. 



(Microfilaria) philippinensis Ashburn and Craig, 1906. 



Ashburn and Craig described this blood filaria in May, 1906. It measures 

 0*29 to 0'335 millimetre in length, has no periodicity, is actively and pro- 

 gressively motile, and is enclosed in a tight-fitting sheath, within which it 

 cannot slip backwards and forwards, and which is only clearly seen at the 

 extremities. The anterior extremity is broad, with a serrated prepuce, and 

 supports a small retractile spicule. The body has an outer striated musculo 

 cutaneous coat and an inner clear portion, with an anterior V-spot situate 

 0'i05 millimetre from the anterior end, and piercing the outer coat by its 

 apex, and opening on the surface. 



The central viscus is seen as a convoluted or spiral tube in the posterior 

 part of the middle third of the body. The tail-spot is in the centre of the 

 posterior third of the body, and opens by the apex of its V on the surface, 

 where there is a distinct papilla. The tail begins to taper at a point midway 

 between the tail-spot and the posterior end, and ends in a fine threadlike 

 point. It is thought that this end disappears during later development. 



The column of nuclei runs the whole length of the worm, being broken by 

 unstained areas here and there. In stained species the V-spots and central 

 viscus are not seen. 



Life-History. — This microfilaria develops in Culex fatigans Wied. On 

 entering the stomach of the mosquito it escapes from its sheath within twenty- 

 four hours, and has pierced the stomach-wall and appeared free in the coelom, 

 where many die, but others develop rapidly, and complete their mosquito 

 eye e. Generally by the third day they have left this position and travelled 



