43O ELIZABETH KIXXEY. 



EXPLANATION OF PLATES. 

 PLATE I. 



Fit;. /. Diagrammatic outline of silk gland of H. cunea. Anterior, middle, 

 and posterior regions of gland numbered I, 2, and 3 respectively. Letters corre- 

 spond to sections taken at these levels. 



FIGS. A-F. Camera lucida outlines of sections from the three regions of a 

 tubule fixed by the Regaud method. Cross sections cut 4 micra in thickness; 

 magnification, oc. 10 X, obj. 4 mm. 



Note: Stippling represents cytoplasm; solid lines represent secretion; broken 

 ines represent intima. 



