42Ó 



NAOKATSU YANAGI AND YAICHIRo OKADA : 



min. long, is tubular with thin membranous wall ; it gradually narrows 

 superiorly from the lower attached end. At the superior end, close to 

 the primary zocecium, the stalk lumen opens externall)' by an aperture ; 

 dorsally to this aperture, the stalk wall is prolonged into a narrow 

 membranous strip. This retains the curvature of the tubular stalk wall, 

 so that it presents a weak arc-like bending in cross-section. It is on 

 the concave side of this membranous strip that the primary zoœcium is 

 attached, at the level of which point the strip is narrowest, being con- 

 stricted on the sides, as it were. It expands above and can be traced 

 for some distance along the bases of the dividing branches, itself 

 dividing in the same way as these, and covering the zocecia of the 

 parts on the dorsal side. 



Zocecia oblong, nearly uniformly wide throughout the length, 

 rounded above, with a so-called " step " on the outer border a little 

 below the middle ; with strongly convex and smooth (without trans- 



Fig. 7. Kinetoskias mitsukurii, n. sp. 



A. Zocecia, one of them with an oœcium. X25. 



15. A small portion of a branch in dorsal view, x 25. 



C. Avicularium in lateral view, x 75. 



