THE PARASITIZED LOCATION OF LARVAL CERCARIA ELEGANS TANG 1992 IN RUDITAPES PHILIPPINARUM AND ITS HISTOCHEMISTRY

This paper reports the results of studies on the organs of parasitized clam by Cercaria el- egans Tang (1992)including the histochemical composition of the larva. Most of the cercariae entered the genital glands of the clam, while only a few invade the digestive organ and its surrounding area. The genital gland is damaged most seriously, being exhausted and extensively occupied by the invading cercariae. In this caes the clam's growth is affected. The main components of the histochemical composition on some larval organs of Cercaria elegans are being noticed as follows: (1) Any wall of daughter sporocyst and tegument of the cercaria contain basic protein and mucoprotein. (2) Germ balls in daughter sporocyst, suckers of the cercaria, germinal primordia and unicellular gland of the cercaria contain DNA positive substances. (3) Excretory bladder of cercaria contain much basic protein. (4) The mid-lateral amd mid-dorsal of cercarial body contain granule-shaped masses mucoprotein and diastase-fast PAS positive substances.