Plate XI. 



Figs, 1-10. Strn/rncn?//j)f/tf< Jtcfernrfinvs T,T, P. 218. 



Till* type-speciiiien (S. C. M. N.\ 409). Nat. size, 

 ilypodermal [leutactin. I.IO x . 

 4. A large and a small stanractinic (Imnalia. ^00 x . 

 Gastral pentactin. 300 x . 



Discoctaster from the deeper part of tlie wall. .300 x . 

 Oxyhexaster from the periphery. 300 x . 

 Same from a deep [)art. 300 x . 

 Microdiscolu^xaster. 'M)0 x . 

 10. Spiculation of the wall. Comhi nation fignre. Ahont 30 x . 



Figs. 11-15. Stanrocahjptus sp. P. 23.5. 



Fig. 11. The entire S})ecimen, attached to a dead I[exa<iiii<-Ua. 2 x. 



Fig. 12. Spiculation of the wall. (Combination figure. 



Fig. 13. Portions of large and small dermal stanractins. 300 x . 



Fig. 14. Oxyhexaster. 300 x . 



Fig. 1;3. Discoctaster. 300 x . 



Figs. 16-22. Acarithascus cactus F. E. Sen. P. 140. 



Fig, IG. Gastral snrfice of a dried specimen, showing the endosomal 

 latticework covering the excurrent canalar a])ertnres. Nat. size. 



Fig. 17. Dermal surface of the same, showing the ectosomal latticework, 

 heneath which are visible the incurrent canalar a])ertures. Nat. 

 size. 



Fig. IS. Portion of a tangential section of the wall, with soft parts stained 

 with Ih'omatoxylin. 300 x . To tlie left, dermal membrane with 

 dermalia, etc. To the right, subdermal trabecuho and spiciiles. 

 Thesocytes visible as masses of fit-like S[»hernles. 



Fig. 19. Reticular chandier-Avall in snrface-view ; with a small group of 

 deeply stained archteocytes. 1000 x . 



Fig. 20. Central uode of a small discoctaster from subdermal region. The 

 central axial cross drawn in as seen in glycerine-uiounted prepara- 

 tions. 10Ö0 X . 



Fig. 21. Peculiar rosette-like groups of deeply stained rod-like or spindle-like 

 bodies, found on soft tissues of a specimen hardened in absolute 

 alcohol and stained with borax-carmine. 1000 x . 



l^'ig. 22. Portion of a section through the wall, with soft parts stained with 

 h.'omatoxylin. Above, the dermal layer or ectosome and the 

 snbdermal space traversed by a pillar. Below and to the right, 

 an excurrent canal with apopyles of cham])ers seen en fare. 

 About 35 x . 



