The morphology of Cercaria sturniae Tanabe, 1948 (cercaria of Gigantobilharzia sturniae Tanabe, 1951), a cause of cercaria dermatitis in Japan.

penetration of the cercaria. It was known for more than ten years by tha name of•gKogan Byo•h(lake side disease) along side Lake Shinji in Shimane Prefecture. According to Tanabe (1951), Cercaria sturniae is the larval form of Giganlobilharzia sturniae Tanabe, 1951, infesting usually in the vein of Sturnia philippensis (Forster) and its first intermediate host being Segmenti na ni ti dell a (Polyphyli s hemi sphaerula (Benson, 1842)). The first description of this cercaria was made by Tanabe (1948) but very briefly. In the early summer of 1951, the authors had an opportunity of making a trip to Shimane Prefacture to collect Segmentina nitidella from infected area. The collected Segmentina was proved to have been infested with this cercaria for about 8%. Following is the description of this cercaria. PARTHENITA : The parthenita of this cercaria is a sporocyst. The mother sporocyst, which only but one specimen was available, is in a slender thread form measuring 1,920ƒÊ long and 170ƒÊ wide, and had 14