PLATE 2 



EXPLANATION OF FIGURES 



Figures 2 and 2a are from an injection of a 7-mni. larva of R. palustris. 

 Figure 2b is somewhat magnified from another specimen. Only blood vessels are 

 seen in figures 2a and 2b. In figure 2, in addition to the blood vessels, the lymph 

 heart plexus (L.Ht.Plx.) is shown spread along the lateral surface of the anterior 

 segments. Its outlet is through the anterior lymph heart (Ant.L.H.) on the third 

 vein (V 3 ). The first and second veins are present with the lymphatics, and dorsal 

 lymphatics (Dsl.L.) extend peripherally. This is the period of primary distribu- 

 tion of outgrowths from the lymph heart plexus. 



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