栉孔扇贝消化管的组织学观察

运用石蜡切片法和组织化学方法，对栉孔扇贝的消化管进行了研究，结果表明，整个消化管从腔内到腔外，都由黏膜上皮、黏膜肌层、结缔组织和外膜组成。黏膜上皮层由纤毛柱状细胞和杯状细胞组成，基膜很薄，皮下有一层有肌纤维，结缔组织中有丰富的血腔隙，除直肠的外膜为浆膜外，其余皆为纤维膜。纤毛和黏液在食物的运输中起重要作用。胃和晶杆囊上皮能分泌消化酶。胃上上有较弱的碱性磷酸酶和脂酶活性。胃和晶杆囊上皮及纤毛有酸性磷酸酶活性，晶杆囊上皮的核前细胞质中含铁，各部位不含钙。

HISTOLOGICAL OBSERVATION OF ALIMENTARY TRACT OF Chlamys farreri

The histological aspects of alimentary tract of Chlamys farreri were examined with the light microscopy and histochemical methods, and the functions were discussed initially. The results show that the entire alimentary tract is a hollow tube surrounded by a wall consisting of four principal layers: epithelial layer, muscularis mucosa, connective tissue and adventitia. The epithelium has two cell types: columnar ciliated cell and goblet cell. The epithelial cells rest on a layer of thin basement membrane, and under the epithelium is a thin layer of smooth muscle fiber. The adventitia is composed of (1) fibrosa, (2) serosa covering the rectum. Numerous blood spaces exist in the surrounding connective tissue, and phagocytes are especially abundant in the stomach. The cilia and the mucus play important roles in the transportation of food particles. Abundant acid phosphatase present in the apical border of the cell, cilia, the lumen of the stomach and the style-sac suggest these cells were actively involved in absorption and intracellular digestion of food material. Weak alkaline phosphatase and lipase activity was detected in the stomach epithelium. Alimentary tract lacks esterase. Fe is found in the cytoplasm in front of the nucleus of the style-sac, and no Ca exists in alimentary tract of Chlamys farreri.