PLATE XIV. 



Figs. 1-4. Microcosmus helleri, Herdman. 



Figs. 5 and 6. Microcosmus propingxias, Herdmau. 



Figs. 7 and 8. Microcosmus pdlymorphus, Heller. 



Fig. 1. Microcosmus helleri, from the left side ; natural size. 



Fig. 2. Part of the branchial sac of the same, seen from the inside, to show the folds ; 

 natural size. 



Fig. 3. Part of the branchial sac of the same, seen from the outside, to show the enor- 

 mous transverse vessel (tr. x.) ; magnified (Hartn., obj. 4). 



Fig. 4. Part of the branchial sac of the same, seen from the inside ; magnified (Hartn., 

 obj. 4). 



Fig. 5. Microcosmus propinquus, from the left side ; natural size. 



Fig. 0. Part of the branchial sac of the same, seen from the inside ; magnified (Hartn., 

 obj. 4). 



Fig. 7. Part of the branchial sac of Microcosmus polymorphus, seen from the inside, to 

 show the folds ; natural size. 



Fig. 8. A portion of the same sac; magnified (Hartn., obj. 4). 



