PLATE 31. 



Eurete erectum Schulze. 

 Figures 1-28. 



1. — Centres and end-rays of two gastral scopules with large-headed, strongly divergent end-rays; 



magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6. 

 2-5. — Side-views of dermal pinules; magnified 200; phot. Zeiss, apochr. 8, compens. oc. 6. 

 6-9. — The distal ends of end-rays of two rather large-headed gastral scopules; magnified 1200; phot. 



Zeiss, H.I. 1/12, compens. oc. 12: 

 G, an end-ray head focussed high; 



7, the head of the same end-ray focussed lower; 



8, the head of another end-ray focussed high; 



9, the head of the same end-ray focussed lower. 



10-12. — The centre and the end-rays of a gastral scopule with large-headed, fairly divergent end-rays; 

 magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6: 



10, focussed high; 11, focussed lower; 12, focussed still lower. 



13. — Part of a large uncinate; magnified 600; phot. Zeiss, apochr. 4, compens. oc. 12. 



14. — A small uncinate; magnified 200; phot. Zeiss, apochr. 8, compens. oc. 6. 



15. — Part of a discohexaster; magnified 600; phot. Zei.ss, apochr. 4, compens. oc. 12. 



16. — Group of scopules from a spicule-preparation; magnified 100; phot. Zei,ss, apochr. 16, compens. 



oc. 6: 



a, two gastral scopules with strongly divergent, large-headed end-rays; b, a dermal scopule 

 with nearly parallel, terminally not thickened end-rays. 



17. — The centre and end-rays of a dermal scopule with fairly divergent, terminally only very slightly 



thickened end-rays; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6. 



18. — An end-ray of a discohexaster; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, q. oc. 10. 



19. — The centre and end-rays of a dermal scopule with nearly parallel, terminally not thickened end- 



rays; magnified 300; phot. Zeiss, apochr. 4, compens. oc. 6. 



20. — A gastral scopule with fairly divergent, large-headed end-rays; magnified 100; phot. Zeiss, apochr. 



16, compens. oc. 6. 



21. — A discohexaster; magnified 600; phot. Zeiss, apochr. 4, compens. oc. 12. 



22. — Part of the gastral membrane with the crosses formed by the lateral rays of the gastral pinules and 



pinule-derivates in situ; magnified 30; phot. Zeiss, planar 20 mm. 



23. — Two gastral scopules with fairly divergent, large-headed end-rays; magnified 100; phot. Zeiss, 



apochr. 16, compens. oc. 6. 



24. — Transverse section through the gastral zone of the tube-wall; magnified 100; phot. Zeiss, apochr. 



16, compens. oc. 6: 



b, lateral rays of gastral pinules; f, skeleton-net; g, gastral spines of the skeleton-net; h, distal 

 rays of the gastral pinules; i, gastral scopules. 



25-28. — Parts of gastral scopules; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, q. oc. 10: 



25, basal part of an end-ray; 



26, distal part of an end-ray; 



27, 28, centres of two different scopules. 



