94 Bulletin American Museum of Natural History (Vol. LIII 
in tracing the development of the parasite through a small amnicolid 
snail. Leiper and Atkinson,! using eggs derived from a dog infected in 
China, were successful in rearing cercariz in the Japanese amnicolid 
Blanfordia nosophora (Robson),? a common snail in the ditches of the 
rice-growing regions and probably the same species as used by Miyairi 
and Suzuki. In 1922 Suyemori found that Blanfordia formosana Pilsbry 
and Hirase acted as the intermediate host in Formosa,’ and later Meleney 
and Faust showed Hemibia hupensis (Gredler) to be the carrier in the 
Yangtze Valley, China.* 
Of the other blood flukes that occur in vertebrates the: life-history 
has been studied in a few cases only. Schistosoma spindale Montgomery, 
a parasite of cattle in India and Sumatra, undergoes its life-cycle in 
Planorbis exustus Deshayes.’ In North America, Bunshiro Tanabe 
recently succeeded in infecting mice with a blood fluke, Schistosomatium 
pathlocopticum Tanabe, starting from cercariz found in the digestive 
gland of Lymnexa palustris Miller found near Boston.° 
Several different types of cercarie are of rather frequent occurrence 
in terrestrial, fluviatile, and even marine mollusks, but in the majority 
of cases their further history is unknown.’ It is, however, evident that 
many species of mollusks, by no means closely related taxonomically, 
may act as intermediate hosts for trematode parasites of vertebrates. 
As far as strictly human parasites are concerned, the hosts at present 
known with certainty belong to the families Lymnaidex, Planorbide and 
Amnicolide. Some of the Melaniide have also been incriminated, but 
on less conclusive evidence. The mollusks of medical importance be- 
long to but few genera and species, although they have been referred to 
under many names. Since there appears to be much confusion with 
11915, Brit. Med. Journ., I, p. 201. 
*Katayama nosophora Robson, January, 1915, Brit. Med. Journ., I, p. 203; Blanfordia nosophora 
Pilsbry, May, 1915, The Nautilus, X XIX, p. 1. It has been claimed that the species is synonymous with 
Hemibia japonica. 
*Suyemori, 8. 1922, Jl. Med. Assoc. of Formosa, No. 220, pp. 1-24 (in Japanese, with English 
résumé, pp. 1-3). 
*Meleney, H. E. and Faust, E. C. 1923. ‘The intermediate host of Schistosoma japonicum in 
China.’ Proc. Soc. Experim. Biol. and Med., XX, pp. 216-218. 
1924. ‘Studies on schistosomiasis japonica.’ Americ. Journ. Hyg., Monogr. Ser., No. 3, pp. 1-339, 
36 Pls. With extensive bibliography and an account of the molluscan intermediate hosts by N. Annan- 
dale (pp. 269-294). Annandale refers all the species of mollusks here called Blanfordia and Hemibia 
to the genus Oncomelania. 
‘Linston, W. G. and Soparkar, M. B. 1918. ‘Bilharziosis among animals in India. The life-cycle 
of Schistosomum spindalis.’ Indian Jl. Med. Research, V, pp. 567-569. 
sTanabe, B. 1923. ‘The life history of a new schistosome, Schistosomatium pathlocopticum Tanabe, 
found in exnerimentally infected mice.’ Journ. of Parasitology, IX, pp. 183-198, Pls. xtv—xx. 
’The following papers deal with cercariz found in African fluviatile mollusks: 
Sonsino, P. 1892. ‘Studi sui parassiti di molluschi di acqua dolce nei dintorni di Cairo in Egitto. 
Festschr. 70. Geburtst. R. Leuckart’s, (Leipzig), pp. 134-146, Pl. xvi. 
Leiper, R. T. 1916. ‘Report on the results of the Bilharzia Mission in Egypt.’ Journ. Roy. Army 
Med. Corps, X XVII, pp. 171-190. 
Nahe C. 1920. ‘A survey of Cawston’s species of South African cercariz.’ Parasitology, XII, 
pp. Ba . 
Cawston, F.G. 1923. ‘South African larval trematodes and their intermediary hosts.’ Trans. 
Roy. Soc. South Africa, XI, 2, pp. 119-130. 
