PLATE VI. 



Figs. 1-4. Salpa musculosa, n. sp. 

 Figs. 5-12. Salpa runcinata-fusiformis. 



at. Atrial aperture. 

 at.m. Atrial muscles. 

 hr.m. Branchial muscles. 

 c.rjr. Ciliated grooves on dorsal 



lamina. 

 d.l. Dorsal lamina. 

 d.m. Dorsal muscles. 

 d.t. Dorsal tubercle. 

 emb. Embrj'o. 



en. Endostyle. 

 m.b. I 



and > Muscle bands. 

 1-10. I 



7i.g. Nerve ganglion. 

 pi(j. Pigment. 

 p.p. Peripharyngeal bands. 

 vise. Visceral mass. 



Fig. 1. Salpa musculosa, from the ventral surface ; natural size. 



Fig. 2. Outline of section of same ; natural size. 



Fig. 3. Dissection of same, showing the muscle bands and various organs ; slightly 

 enlarged. 



Fig. 4. Anterior part of last ; more enlarged. 



Fig. 5. Salpa runcinata-fusiformis, aggregated form, from Antarctic, Station 152 ; 

 seen from dorsal .surface ; natural size. 



Fig. 6. Salpa runcinata-fusiformis, aggregated form, A'ariety, from North Atlantic, 

 April 26, 1876 ; natural size. 



Fig. 7. Same species, dissection of anterior dorsal part ; x 2. 



Fig. 8. Part of dorsal lamina ("gill") of .solitary form of same species (S. 1). 



Fig. 9. Small part of edge of last ; higlilv magnified to show ciliated grooves, etc. 



(S- *)■ 

 Fig. 10. Ciliated cells from last. 



Fig. 1 1. Dorsal tubercle and neighbouring parts of Salpa runcinata -fusiformis, 

 aggregated form (S. 1). 



Fig. 12. Arrangement of muscle bands in Salpa runcinata-fusiformis, aggregated 

 form; from South Atlantic, February 12, 1876 (S. 1). 



