NOBUAKI AKAO, SETUKO TSUKIDATE, AND KOICHIRO FUJITA
Department of Medical Zoology, School of Medicine,
Tokyo Medical & Dental University
1-5-45, Yushima, Bunkyo-ku, Tokyo 113, Japan
KAORU KONDO
Department of Parasitology, School of Medicine,
Kanazawa University
13-1, Takara-machi, Kanazawa 920, Japan