MONOGRAPH OF THE EXISTING CBINOIDS. 



65 



CENTRAL CANAL 



, MUSCULAR FOSS^ 

 ^NTERARTICULAR LIGAMENT FOSS-C 

 ^TRANSVERSE RIDQE 

 5 DORSAL LIGAMENT FOSSA 

 iBASAL RAYS 

 JRADIAL RIDGES 

 CIRRUS SOCKETS 



INTERRADIAL RIDGES 



DORSAL POLE 



Fig. 9. 



MUSCULAR FOSS/E 



uOAME^f^ prr 



INTERART1CULAR LIQAMEM* FOS&C 

 ■CENTRAL CANAL 



TRANSVERSE RIDOB 

 DORSAL LIQAMENT FOSSA 

 CENTRO- DORSAL 



CIRRU5 SOCKETS 



Fig. 10. 



DORSAL LIGAMENT F06Si\ 

 TRANSVERSE RtDOB 

 CENTRAL CANAL 



CENTRO-DORSAL 

 LtOAMENT PIT 



'MUSCULAR FOSS^ 



ROSETTE 



BASAL RAYS 



Fig. U. 



Fig. 12. 



'^> 



ENTRAL CAVITY 



Fig. 13. 



\ 





I Bri (FIRST PRIMIBRACM 

 RADIALS 



SVZYGIES 



SVNARTHRIES 

 WATER PORES 



CENTRO-DORSAL 



Fig. U. 



Figs. 9-14.— 9, Latebal view of the centrodorsal and raduls of a specisiex of Stenometr.v quinhue costata from 

 THE Ki Islands (adapted from P. H. Carpenter). 10, Lateral view of the centrodor-sal and rabials of a speci- 

 men OF Himerometra maktensi from Singapore (drawing by the author). 11 , Ventral view of the radial penta- 

 gon OF A specimen of Himerometra marten.si from Singapore (drawing by the author). 12, Dor-'^al view of the 



RADUL PENTAGON OF A SPECIMEN OF PTILOMETEA MCLLERI FROM SYDNEY, NEW SOUTH WALES (DRAWING BY THE AUTHOR). 



13, Ventral \nEW of the centrodorsal of a specimen of Peeometra diomede.e from southern Japan (drawing by 



THE AUTHOR). 14 , DIAGRAMMATIC LATERAL VIEW OF THE PROXIMAL PORTION OF A SPECIMEN OF ATELECRINUS CONIFER FROM 



THE Hawaiian Islands (drawing by the author). 



