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The cells of the intestine have large nuclei. The 

 protoplasm is finely reticular, and stains less deeply 

 than that of the cells of the mid-gut. Stained with 

 Heidenhain's haematoxylin, no granules are present as 

 in the cells of the mid-gut. They have no striated 

 border. 



In the rectum the cells become small and flattened. 

 There are here, however, bodies usually termed rectal 

 glands. These are papillae covered with a single layer 

 of much hypertrophied cells resembling those lining 

 the small intestine and colon. 



The Salivary Glands. The salivary acini lie in 

 a cleft in the fat-body, which latter comes in close 

 contact with the glands. Each gland acinus consists 

 of a single layer of large cells, limited externally by a 

 delicate sheath (basement membrane) and internally 

 by the intra-glandular duct wall. 



In Anpfhelines the intra-glandular duct becomes 

 larger as it approaches the termination of the acinus, 

 and forms a large cavity. 



In Culicines the duct remains of the same diameter 

 throughout the acinus, and terminates abruptly near 

 the end of the acinus without any dilatation. 



In both Culicines and Anofihelines there are two 

 types of gland acinus. These are recognizable both 

 in the fresh gland and in fixed specimens. From their 

 appearance in the latter they may be termed 



(1) The granular type. 



(2) The clear or colloid-like type. 



The Granular Type. The greater portion of the 

 acinus consists of cells whose nucleus and protoplasm 

 has been pushed to the outer portion of the cell by a 

 large mass of secretion which occupies almost the 

 whole of the cell. In the fresh gland this secretion 

 appears as a clear, refractive substance, and can, by 



