PLATE 3 



EXPLANATION OF FIGURES 



G A longitudinal section of the body wall of the dorsal surface, showing the 

 position of the various excretory vessels with reference to the muscular layers. 

 Heron, corrosive, iron-haematoxylin. X 240. 



7 Bod}^ wall from a transverse section near the center of the ventral surface, 

 showing the uni-cellular glands (?); chromic acid, iron-haematoxylin. X 1100. 



8 Two sense organs of the cuticle from the dorsal anterior region of the body. 

 X 1100. 



9 Part of one of the fibers of the inner longitudinal muscle of the body wall, 

 showing the alternation of stained and unstained substance. Heron, corrosive, 

 iron-haematoxylin. X 560. 



10 Myoblast and its nucleus and adjoining muscle fibers of one of the longitu- 

 dinal parenchyma muscles. Heron, chromic, iron-haematoxylin. X 1100. 



11 Part of one of the parenchyma muscles from the same series as fig. 9. X 1100. 



12 From a section passing vertically to the posterior region of the oesophagus. 

 Heron, chromic. X 560. 



13 Section from a fully matured worm vertical to the wall of the intestine, 

 showing the pseudopodial inner borders of the epithelium; the darker shading of 

 the deeper ends of the cells indicates the distinction between the stained and little 

 stained parts of the cell, corrosive, iron-haematoxylin. X 1100. 



13 a Free hand drawing from a living worm from bass, showing the lateral 

 pouches of the intestinal caeca. 



14 The epithelium of the intestine from an immature worm showing resting 

 stage of the tissue. Corrosive, iron-haematoxylin. X 1100. 



15 Reconstruction from several adjoining sections of a frontal series, showing 

 the relation of the collecting to the subcuticular cavities and to the bladder, also 

 the recurrent vessel and the intestine. X 36. 



16 Free hand drawing from the posterior ends of the chief excretory vessels 

 as seen in a living worm from the bass under slight compression. X Zeiss oc. 2, 

 ob. A. 



17 Reproductive system as seen from the ventral surface, from total prepara- 

 tions. The vitellaria have been omitk'il. 



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