4 ART. 2. — H. MATSUMOTO : 



h. Those which are divided into lialves by a series of small 



pores or by a moniliform pore, are found in those forms 



in which the dorsal side of the arms is entirely protected. 



E. g. Microphiura ; Ophiologimus ; Ophlothamniis emend. ; 



" Ophiactis " pars, i.e. my Ampliiadis ; " Ophioconis " pars, 



i.e. my Ophiuroconis and Ophiurodon ; Astroph'nira ; àa, 



4. Those forms with quadrangular and stout teeth have oral 



frames with well developed lateral wings for the attachment of 



voluminous masticatory muscles. E. g. Amphiuridce mihi ; Opino- 



trichidœ ; Ophioceramîs ; Ojjhionereidinœ mihi ; and Ophiocomidœ. 



B. Systematic. 



1. Astrocevas, Trichaster and Eurycde have a certain common 

 structure, by which they may be distinguished from either Asteronyx 

 or Aster oschema. 



2. Astrotoma and its allies have a certain distinctive character 

 in contrast to Asteroporpci, Astrochele, Gorgonocephahis, Astroden- 

 drum, Astnocladus and their allies. 



3. The Amphiuridce mihi and Ophiotrichidœ stand in a very 

 intimate relation in ther internal structures. 



4. " Ophiactis " pars, i.e. my Amphiactis is a connecting link 

 between the Ophiaccmthidœ and Amphiuridce. 



5. The Ophiolepididce, Ophiodermatidce and Ophiocomidœ form 

 together another compact group. 



6. The " Amphiuridce " pars, i.e. my Ophiochitonidce are by 

 no means allied to the genuine Amphiuridce, but are very near to 

 the Ophiodermrdidce and Ophiocomidce. 



7. Ophiopsila is, as a matter of fact, notliing else than an 

 ally of the Ophiocomidce. 



8. " Ophioconis " pars, i.e. my OphiuTOConis and Ophiurodon, 



