EiTTEB. — Octacnemus. 



PLATE 3. 



Fig 8. Comparison of this witli Figure 1, Plate 1, will sliow at a glance what the 

 dissection is. The visceral mass is here somewhat too large for the 

 size of the animal as a whole. 



Fig. 9. The anterior portion of the piece cut from the dorsal wall of the branchial 

 sac seen from the inner surface (see Fig, 3, PI. 2). 



