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Nephrocytes of Pediculus 
The nephrocytes, when examined alive (Fig. 2), are seen to contain numerous 
droplets of variable size, which are of a greenish colour. These droplets are 
larger and more numerous in fasting lice. The size of the droplets at times 
exceeds that of the nucleus, which may consequently be obscured. The 
droplets are not dissolved and not decolourized by 80 per cent, alcohol or by 
weak acetic acid. 
The nephrocytes are linked to each other by very fine connective filaments 
and they have no duct or the like which communicates outwardly or with the 
alimentary canal. 
Fig. 1. Peri-oesophageal nephrocytes of P. humanus in section (fixed in Carnoy, stained by 
iron - haematoxylin). 
Fio - . 2. A living nephrocyte of P. humanus slightly compressed, showing two nuclei, N, and 
green droplets, g.d. 
Disseminated Nephrocytes in Pediculus. 
To examine these structures, the living insect should be opened and the 
fat bodv removed and spread in a drop of normal salt solution. The specimen 
is then covered lightly with a cover-glass and examined microscopically. The 
large polynuclear cells of the fat body, filled with fat droplets, are seen to be 
connected by much smaller cells. These cells are binucleate and in respect to 
their protoplasmic structure and inclusions conform to the above described 
peri-oesophageal nephrocytes, but for their disposition and shape (Fig. 3). 
