6 ART. 7. — K. KISHINOUYE. 



without muscular fibres in the tseniola. Structure of the genital 

 gland not simple. 



Schizodiscus nagatensis. 



(Figs. 3-6.) 



Lucernaria nagatensis, Oka, 1897. In : Zool. Mag. Tokyo, Vol. 

 IX, pp. 1-4, pi. I; Annot. Zool. Jap. Vol. I, pp. 141-145, 



with woodcuts. 



The umbrella is of an extraordinary form. It is not goblet- 

 shaped, but quite Hat and deeply divided. The animal, whin 

 fully expanded, is about five times as broad as long. The eight 

 adradial lobes or arms are somewhat recurvate. They are united 

 in pairs and the four perradial arches are about twice as deep 

 and wide as the four interradial arches. 



The peduncle is short, being subequal in length to the 

 umbrella, and more or less conical in shape. It is four-chambered ; 

 but in young specimens it is one-chambered, the tseniola 

 being separate. These begin to unite near the pyloric portion. 

 In the peduncle we find no muscle, as we do in the case of 

 Craterolophus tethys. The adhesive surface of the peduncle is 

 more or less quadrate and has many small furrows beside four 

 large interradial furrows (fig. 5). 



The exumbrella is quite smooth in the calyx, but shows a 

 slight rugosity in the peduncle owing to the presence of many 

 small groups of nematocysts. In an old specimen, I have found 

 that the surface of the peduncle is divided into numerous small 

 areas by a network of grooves. The surface looks as if paved. 

 The exumbrella consists of three layers : a layer of columnar 

 ectoderm cells, a firm gelatinous layer and a layer of glandular 



