MALARIA EXPEDITION TO NIGERIA 33 
In stained specimens (plate VI, fig. 1) the cuticle is also well marked. The 
worm measures ii9*3m in length. The embryos on fixing take up no characteristic 
position. At the head end the cell column is bifid. Four 'spots' are generally 
made out : 
1. Slit like, at a distance of 29-2 per cent, of total length. 
2. A small lateral bay ; distance 42*6. 
3. An oval-shaped spot occupying the breadth of the worm, containing 
only a few small nuclei ; distance 64-4. 
4. A small lateral break; distance 89'9- 
The two lateral spots (2 and 4) are on the same side of the worm. All the 
spots are constant, but the first and second are sometimes badly marked. 
Filaria falciform is. Nov. Sp. 
Definitive Host : Cinnyris fuliginosa. 
Site. The subcutaneous tissue of the back of the head, dorsum of wing, root 
of neck, and leg. 
In one bird of this species three males and two females were found ; in the 
second, one male and one female (with adult forms of F. bibulbosd) ; in another, 
one male and three females (also with some adults of F. bibulbosd), and in the fourth, 
one male and three females. 
The female varies in length from 207 to 29*4 mm. ; its breadth is about 
0*23 mm. 
— , 0-58, 076 , 287, 98-9 
Lobb s formula : 7 —5 7 — 
, 0'Q2, O-02, 0*69, 0-31 
It is creamy white in colour ; a long thin worm with a slightly curved tail end. The 
transversely striated cuticle is finely ridged, the ridging disappearing near the head end. 
The head end (plate VII, fig. 2) is bluntly rounded, and tapers slightly. The mouth 
is terminal, and is simple, bearing no papillae. The oesophagus is a straight thick- 
walled tube, and has no bulbous ending ; the intestine commences suddenly as a 
broad tube full of dark granular substance, with here and there large irregularly 
angular masses of orange-coloured material. The position of the anus is on an 
average at 0^38 mm. from the posterior end ; the orifice is at the summit of a low 
flattened papilla. No anal papillae can be made out. The body rapidly tapers 
beyond the anal aperture and ends in a cone-shaped portion 0*047 mm. across at its 
base (plate VII, fig. 3). The vulva is situated at 0-774 mm. from the head end of 
the worm, at the apex of a nipple-shaped papilla. The vagina courses down the 
worm, or may make a twist upon itself: it divides at about 1*5 mm. from its orifice 
into the two uterine horns, which, coiling many times on themselves, occupy almost 
the whole of the coelomic cavity. They end in a somewhat similar manner to that 
described under F. spiralis, except that no evidence of the existence of a ' pylorus ' 
can be made out, and moreover, the extreme end is not bulbous. 
E 
