MONOGRAPH OF JAPANESE OPHIUROIDEA. 61 



Astroiliorax Döderlein, 1911. 



Astrotoma Lyman, 1878. 

 J>. Arms divided a few times. 



Astrocolon Lyman, 1879. 

 Lyman, ^yl^oso erroneous interpretation of certain parts in 

 Euryale aspsra was pointed ont before, has made a similar mistake 

 in the present family, inasmuch as he states that, in Astrocnida 

 isiclis (Duchassaing), Gorgonocephalus arcticus Leach \_:=Ct. agasski 

 (Lyman)] and G. chilensis (Philippi), the genital slits are not sur- 

 rounded by any " bursa " but directly penetrate into the " peri- 

 toneal cavity," in which the generative glands lie. I have studied 

 the internal structure of Astrochele lymani Verrill, Asteroporpa 

 hadracantha Clark, Gorgonocephalus tuberosus Döderlein, G. arcticus, 

 G. caryl (Lyt^ian), G. dolichodactglus Döderlein, Astrodendrum saga- 

 minum (Döderlein), Astrocladiis annulatus Matsumoto, A. coniferus 

 (Döderlein), Astrohoa arctos Matsumoto, Astrothamniis echinaccus 

 Matsumoto and Astrotoma sohrina Matsumoto, and am convinced 

 that, Lyman's " peritoneal cavity " is not the genuine peritoneal 

 cavity but merely the genital bursa), which are very spacious and 

 communicate with each other, and usually also with the perihœmal 

 canal, so as to form a single compound cavity ; the genuine peri- 

 toneal cavity is perfectly divided into five radial compartments, 

 which are entirely filled up by the very voluminous, folded gene- 

 rative glands, and no longer appear as cavities ; the generative 

 glands do not lie in Lyman's " peritoneal cavity," i.e. genital bursa?, 

 but are separated from them by a thin but distinct membrane 

 and lie morphologically outside them. As I have already pointed 

 out in Euryale aspera, the fact that the brachial body cavity, 

 which is the direct continuation of the true peritoneal cavity, 

 has no direct communication with Lyman's " peritoneal cavity," 



