PACIFIC TUNICATA OF U.S. NATIONAL MUSEUM 



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Figure 10. — Amaroucium crateriferum Sluiter: a, right side of thorax; b, right side of 

 abdomen of same zooid; c, right side of posterior part of postabdomen of same zooid; 

 d, frontal side of stomach; e, transverse section of postabdomen. 



at the end of a short sii^hon and with a long atrial languet ending in 

 a trifid tip. About 25 longitudinal and about 20 transverse muscles 

 on each side of the thorax. From 20 to 24 stigniatal rows, up to 20 

 stigmata in each row. Horizontal membranes well developed along 

 transverse vessels. Six large tentacles, besides some smaller ones? 

 Ciliated groove an oval opening. Dorsal languets of a moderate 



