THE GEPHYREA OF JAPAN. 



the external apertures of which lie slightly in front of the anus, 

 are toterably long, corresponding in length to nearly one half of 

 the body proper. They are of a deep brownish color and are 

 entirely free from the body-wall except at the anterior end. I'he 

 sexual organs (sx) are developed as two narrow transverse bands 

 placed across the bases of the ventral retractor muscles. 



Habitat : This species is common along the coasts of the 

 Tokyo and Sagami Bays. It occurs very abundantly in shallow 

 waters near the Misaki Marine Laboratory. The animals live in 

 clean sand, mostly in narrow fissures of rocks. No specimens 

 have thus far been obtained at any other locality than those 

 mentioned above. 



PHASCOLOSOMA MISAKIANUM, n. sp. 



(Figs. 3, 30-33). 



This species is small and slender. The total length of the 

 animal with the introvert wholly protruded, measures about 5 cm., 

 the thickest part of the body proper rarely exceeding 2 mm. in 

 width. The introvert corresponds in length to about four-fifths 

 of the total length. The skin is smooth, thin and somewhat 

 transparent ; it is of a yellowish pink color (Fig. 3 ). Under 

 high magnification there can be detected numberless small papillary 

 bodies distributed all over the body-surface. In the posterior 

 region of the body, Avhere these bodies are most closely aggregated, 

 they measure 0.03 ??^w. in both height and diameter. Here they 

 take the shape of a small rounded cone, on the summit of which 



