12 
Filaria loa 
posterior to the third pair. If we could not discern the interior structure 
we should simply note slight undulations of the cuticle instead of 
papillae. 
The cuticle is non-striated with the exception of that covering the 
posterior extremity. Here transverse striae are perfectly discernible 
and, by focussing, they may be seen to extend across the entire width 
of the body at this portion. Upon close observation it may be noted 
that the outer and thinner epiderm is not striated. 
Internal structu7'e. Beginning at the oral orifice is the oesophagus, 
formed by large cylindrical cells. On either side there is a dark 
granular mass due to nerve cells and probably to some glandular 
elements. For a distance of 0 2 mm. the lateral bands and the 
powerful musculature may be observed with considerable clearness 
when the beginning of the intestine, the testicle, and greater thickness 
of the body make the internal parts less easily discerned. However, 
the intestine and the te.sticle can be determined throughout the entire 
body. In the anterior part the testicle is composed of spermatoblasts 
of polyhedral shape. Lower in the posterior portion free spermatozoa 
occur. 0T14 mm. above the ano-genital opening when viewed from 
the left side we observe the upper thicker end of one of the spicules. 
It appears to be transversely concave, and transversely striated near 
its upper end. Upon close study we are not sure but that these coarse 
striae are caused by the spermatozoa in the adjoining ejaculatory duct 
where they occlude the light from passing through the highly retractile 
and dense edges of the chitinous spicule. The spicule gradually 
diminishes in size and curves towards the anal opening just before 
reaching which it is lost to view. Neither spicule projects from the 
ano-genital opening. It is 0'28 mm. from the tip of the posterior 
extremity of the body to the base or anterior end of the longer 
spicule. 
Upon turning the worm over and examining it from the right side 
a shorter spicule, like the lower end of the long one, is seen partially 
crossing the longer one just inside the ano-genital opening. 
Anterior to the anus there are three of the five pairs of papillae. 
They are distinct pyriform masses projecting from the musculature and 
cause the papillae noted when examining the cuticle. These papillae 
do not protrude from the skin so much as their interior granular 
portions protrude as distinct pyriform projections from the musculature. 
Billet suggests that the largest pair may give rise to a secretion of 
some aid to the act of copulation. The anterior pair are situated 
