W. Nicoll 393 
in Japan and Korea represents a distinct species which he named Triclio- 
strongylus orientalis. Other species of this genus which have been reported as 
occasional parasites in man are 1 . vitrinus Rooss 1905 in Egypt, T. _ probolurus 
(Eailliet 1896) also in Egypt and 7 . colubriformis (Giles, 1892) (which is usually 
referred to as Strongylus subtilis or T. instabilis). It would thus appear that 
four distinct species of this genus may be occasional or even common para¬ 
sites of man. Their small size and inconspicuous appearance render their 
detection a matter involving more than usual care. A somewhat similar, 
though larger, cattle Nematode, Haemonchus contortus, was reported as a 
human parasite in Brazil by Magalhaes in 1908. These worms must be taken 
into account in human pathology as potential causes of anaemia and enteritis. 
Another worm of considerable economic importance is the kidney worm 
of swine (Stephanurus dentatus). This is yet another case in which it has been 
demonstrated that infection may take place through the skin (Bernard and 
Bauche, 1914). 
Allied to the rat tumour Spirojrtera, to which reference has already been 
made, is a worm of greater economic importance, namely, Spiroptera (Spirura) 
sanguinolenta, a not uncommon parasite of dogs in certain parts of the world. 
Following the work of Grassi in 1888 it was tentatively accepted that the 
larval stage of this worm occurs in the common cockroach ( Blatta orientalis). 
beurat (1912), however, maintains that this larva is that of Spirura talpae, 
a similar parasite of the mole, and that the larvae of S. sanguinolenta occur 
encysted in fowls, hedgehogs and lizards, a somewhat extraordinary variety 
of intermediate hosts. 
The last matter of Public Health interest which need be dealt with here 
is that of house-flies as carriers of parasitic infection. Since 1911, when I 
published some experimental observations on this subject, Shircore (1916) and 
Wenyon and O’Connor (1917) have confirmed these results by observations 
under natural conditions. Shircore found eggs of Tricliocephalus dispar , Taenia 
saginata , Ancylostoma duodenale, and Ascaris lumbricoides in or on flies from 
hospital wards in British East Africa. Apparently 10-12 per cent, of these 
flies were functioning as natural u carriers.” Wenyon and O’Connor examined 
the faeces of wild ’ flies under natural conditions and found eggs of Taenia 
saginata , Ancylostoma duodenale , Trichoceplialus , Heterophyes and lateral- 
spined eggs of Bilharzia. These observations in conjunction with the classic 
experiments of Grassi and Calandruccio leave little doubt that house-flies 
play an actual part in the dissemination of worm infection, particularly of 
such forms as Trichoceplialus and Ascaris. Buxton (1920) also recorded the 
natural occurrence in flies of eggs of Hymenolepis nana, Strong yloides, etc. 
A\ ith regard to the medicinal treatment of parasitic worm infections a few 
notes only are necessary. The most extensive work on this subject is that of 
Hall (1919—1920) who has experimentally tested the value of various anthel- 
minthics. 1 erhaps the most important new treatment is the use of carbon 
tetrachloride in ancylostomiasis. Results appear to show that this is the most 
