155 



rods in 0. fusus. If it should ultimately be proved that these two larvae 

 are really nearly related, it will be a fact of considerable importance, 

 showing that also within the genus Ophiura, even as recently restricted 



c. 



Fig. 83. Ophiopluteus fusus. A. specimen in metamorphosis; ""/i- B. body skeleton of the 

 same; C. outer part of posterolateral rod. '*7i- Letters as in fig. 61. 



by Matsumoto and H. L. Clark, different groups of larvae may occur. 

 The fact that the larvae of the two species 0. alhida and texturata are so 

 different would then prove that these species are not so nearly related as 

 hitherto supposed; the other conclusion that might be drawn, viz. that 

 the larvae cannot show anything regarding the natural affinities, is much 

 less probable, considering the facts brought to light in the present work. 



20* 



