PLATE VII. 



Figs. 1-5. Boltenia elegant;, Herdman. 



Figs. 6-8. Boltenia pachydermatina, Herdman. 



Fio-. 1. Boltenia elegans, from the right side ; natural size. 



Fig. 2. Part of the branchial sac of the same species, from the inside, showing parts of 



two folds (br.f.), and the transversely placed stigmata in the interspace 



(Hartn., obj. 4.) 

 Fig. 3. The peritubercular area and dorsal tubercle, from the inside ; natural size. 

 Fig. 4. Dissection of the left side of the body, to show the alimentary canal and genital 



organs, from the right side ; natural size. 

 Fig. 5. The right side of the mantle, from the inside, showing the genital gland, and the 



network of muscle bands ; natural size. 

 Fig. 6. Boltenia pachydermatina, a small specimen, from the right side ; natural size. 

 Fig. 7. Part of the branchial sac, from the inside ; magnified (Hartn., obj. 4). 

 Fig. 8. The surface of the dorsal tubercle ; much enlarged. 



