RHIZOCEPHALA — REINHARD 



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Figure 4. — a-d, Galatheascus minutus Boschma: a, external appearance of specimen on 

 Munidopsis barbarae; b, transverse section of the same specimen; t, testes and vasa defer- 

 entia of specimen on Munida stimpsoni; d, chitinous linings of vasa deferentia revealed by 

 maceration of another specimen on Munida stimpsoni; e, Tortugaster fistulatus Reinhard, 

 external appearance of specimen on Munidopsis spinifer. Abbreviations: sh, sheath; vd, 

 vas deferens; others as in figure 1. 



Serial sections of the other parasite occurring on M. stimpsoni and 

 of the Blake specimen were prepared. No differences were observ- 

 able in the details of their internal anatomy. 



The mesentery begins just behind the mantle opening and gradu- 

 ally increases in width as it passes backwards. It reaches its maxi- 



