12 
THOMPSON YATES LABORATORIES REPORT 
alimentary canal, and bear two small lateral sack-like structures at the base of the tail. 
They swim actively and may live for days in muddy water and damp soil. They are 
said by some authors to escape only by rupture of the adult worm, but according to 
Manson 1 they are emitted by a prolapsus of the uterus through the mouth. The 
mature worm drills a hole in the derma. Over this the epidermis forms a bulla, which 
ruptures in a few days, disclosing a small superficial ulcer with a hole at its centre, 
under which lies the head of the worm. On the application of water to the ulcer, a 
minute quantity of whitish fluid is extruded, seen on microscopical examination to 
be swarming with embryos ; or a little tube, the prolapsed uterus itself, is sometimes 
seen protruding. In about a fortnight the whole uterine contents are emptied. It is 
usually asserted that the female alone is known, and that it is uncertain whether it is her- 
maphrodite or whether both sexes are present in the Cyclops. Charles 2 has described 
a specimen found in the mesentery of a human subject from an orifice in the middle of 
the body of which he drew out a much smaller specimen, which may have been the male. 
Life history. The young embryos in water attack a fresh-water Cyclops 
and penetrate through the interarticular membrane between the abdominal plates into 
the body cavity. Here the intestine of the parasite further develops, and on the 
eleventh day they moult and exhibit a very changed appearance, being shorter 
(o - 5 mm.) and non-striated. In four weeks they measure I mm. in length. They 
are thought to reach man again through the medium of drinking water containing 
infected Cyclops : the parasite being able to pierce the tissues to reach its usual 
site in the legs. Chapotin and others claim that the embryos can enter the body 
through the skin. Plehn 3 reports to have fed two monkeys on bananas covered 
with embryos, and that one of them subsequently developed a painful tumour of the 
thigh and died after eight and a half months. The tumour contained a worm in all 
respects identical with F. medinensis, though only 4*0 cm. long. 
Filaria lentis. Diesing 
Syn. F. oculi humani, Von Nordmann. Under this title are included nema- 
todes, found on several occasions in the eye of man. Those described have varied 
considerably in length, 1-72 to i2 - 6 mm. Railliet 4 considers that they represent 
worms of different species which have gained access to the wrong host, or such as have 
been arrested in their development. Specimens have been described by Von Nord- 
mann, Gescheidt, and Scholer. 
Filaria inermis. Grassi 
Syn. F. palpebralis, Pace, nec Wilson; F. peritonei hominus, Bates; F. con- 
junctivae, Addario. The female only is known. It measures about 160 mm. long 
1. Manson, Tropical Diseases. 1900 p. 554. 
2. Charles, a Contribution on the Life History of the male Filaria Medinensis, founded on the examination of specimens 
removed from the abdominal cavity of man. Scientific Memoirs, by Medical Officers of the Army of India. 
Part vii. Calcutta, 1898. 
3. Plehn, Die Kameru-Kuste, etc. Berlin, 1898. p. 295 
4. Railliet, Trait/ de Zoologie Medicale et Agricole. Paris, 1895. p. 529. 
