74 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



PYURA INFLATA, new species. 



Body of the only specimen egg-shaped, larger and more rounded 

 at the posterior end. From the anterior end, somewhat toward the 

 ventral side, there arises a stout cylindrical pedicel of almost uniform 

 diameter throughout its length, which does not equal that of the 

 body. Branchial aperture of moderate size, square, raised on a very 

 short tubular prominence arising from the anterior dorsal region. 

 Atrial aperture very large, rounded, but little raised above the sur- 

 face of the body and situated in the posterior dorsal region. Test 



n is 



Pigs. 12-18. — Pyura inflata, new species. 12, Right and left sides of body. On»- 

 hai-f natubal size 13, outline of body showing muscle bands on mantle. one- 

 half natural size. 14, medium-sized tentacle. x 12.5. 15, dorsal tubercle and 

 part of dorsal lamina. x 12.5. 16, part of liver. x 35. 17, end of rectum 

 showing anal lobes. x 8. 18, part of gonad. x 12. 



thin, tough, and parchmentlike, nearly smooth externally and of a 

 yellowish white color. Outer layer of pedicel similar to the test 

 covering the body; internally the pedicel is partly hollow, the re- 

 mainder being filled with test substance of rather soft consistency. 



Mantle thin, very strongly adherent to the test. Conspicuous 

 muscle bands are few, comprising only a few circular bands about 

 the apertures (especially about the branchial aperture), and some 

 rather short straight bands running in a dorso-ventral direction on 

 each side of the body, but ending abruptly after extending about 

 halfway down the sides. They are mostly gathered into groups of 



