PLATE 23. 



Holascella taraxacum Lendenfeld. 

 Figures 1-3. 



1. — Portion of the distal part of a longitudinal ray of a large choanosomal hexactine; magnified 600; 



phot. Zeiss, apochr. 4, compens. oc. 12. 



2, 3. — Two distal ends (anchor-heads) of anchoring spicules; magnified 600; phot. Zeiss, H. I. apochr. 2, 



compens. oc. 6. 



Holascella ancorata Lendenfeld. 

 Figures 4-25. 



4. — A part of a ray of a principal tetractine where regeneration took place; magnified 600; u. v. phot. 



Zeiss, q. monochr. 6, q. oc. 10. 



5. — A microdiscohexactine; magnified 200; phot. Zeiss, apochr. 8, compens. oc. 6. 



6. 7. — The central parts of a microdiscohexactine (fig. 6) and a hemidiscohexaster (fig. 7); magnified 



2000; u. V. phot. Zeiss, q. monochr. 1.7, q. oc. 10. 



8. — A microoxyhexactine; magnified 200; phot. Zeiss, apochr. 8, compens. oc. 6. 



9. — View of the specimen; magnified 1.4; phot. Zeiss, anastig. 167 mm. 



10. — Portion of a group of microscleres from a spicule-preparation ; magnified 600; phot. Zeiss, H. I. 



apochr. 2, compens. oc. 6: 



a, a ray of a microdiscohexactine; b, rays of microonychhexactines. 



11. — The distal part of a ray of a microonychhexactine; magnified 2000; u. v. phot. Zeiss, q. monochr. 



1.7, q. oc. 10. 



12. 13. — The distal ray of two superficial hexactines; magnified 200; phot. Zeiss, apochr. 8, compens. 



oc. 6: 



12, of a hypodermal hexactine; 13, of a hypogastral hexactine. 

 14. — Group of microscleres from a spicule-preparation; magnified 200; phot. Zeiss, apochr. 8, compens. 

 oc. 6: 



a, microdiscohexactines; b, a microonychhexactine. 

 1.5. — Fragmentary onychhexasters ; magnified 200; phot. Zeiss, apochr. 8, compens. oc. 6. 

 16. — A ray of a microonychhexactine; magnified 600; phot. Zeiss, apochr. 4, compens. oc. 12. 

 17-25. — Six distal ends of rays of discohexasters, hemidiscohexasters, or microdiscohexactines; magni- 

 fied 2000; u. V. phot. Zeiss, q. monochr. 1.7, q. oc. 10. 

 Of four there is only one view (figs. 19-22). Of one (figs. 17, 18) there are two views (fig. 17, focussed 

 lower, fig. 18, focussed higher), and of another (figs. 23-25) there are three views (fig. 23, focussed high, 

 fig. 24, focussed intermediate, fig. 25, focussed low). 



