147 



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, 

 refractile substance, and can, by pressure, be made 

 to exude from the cell in refractile globules. In 

 specimens hardened in alcohol, this clear secretion 

 appears as a granular mass, occupying the greater 

 portion of the cell. It stains faintly with haema- 

 tein, and shows under high powers (one-sixteenth 

 oil immersion) a coarse reticulum and isolated 

 globules, an appearance probably due to the pre- 

 cipitation or coagulation of the secretion by the 

 alcohol. Considerable variations exist, however, 

 in the appearance of this granular secretion, both 

 in the different mosquitoes and in different parts 

 of the same gland. In Anophelines the greater por- 

 tion of the gland contains cells densely crowded 

 with granular material. Very frequently, how- 

 ever, the terminal portion contains cells in which 

 only a few large globular masses exist (Fig. 38). 



The protoplasm of the cell occupies, in the 

 fully-matured gland, only the extreme periphery, 

 and the nucleus, which is much degenerated, is 

 pushed to the outer portion of the cell, and usually 

 lies in the angular interval left at the base of two 

 or more contiguous cells. In the granular type 

 of gland this disappearance of the protoplasm and 

 nucleus from view is more pronounced than in the 

 clear type of gland. 



The Clear or Colloid-like Type. — Of the last- 

 mentioned type there are two acini upon either 

 side ; of the present type there is but a single 

 acinus upon either side, which usually lies between 

 the two acini of granular type (Fig. 38). 



In the fresh gland the cell outlines are not so 



