PLATE 5. 



Erylus rotundus Lendenfeld. 



Figs. 1, 3, 11-13. 

 Figs. 2, 4, 17. 

 Figs. 5, 26-28, 31. 

 Figs. 14, 15. 

 Figs. 16, 30. 

 Figs. 18-22, 32. 

 Fig. 23. 



- var. typica Lendenfeld. 

 ■ var. typica Lendenfeld. 



var. cidaris Lendenfeld. 



var. typica Lendenfeld. 



var. typica Lendenfeld. 



var. megarhabda Lendenfeld. 



var. megarhabda Lendenfeld. 



Form D. Northeast Hawaii. 

 Form B. Kauai. 



Form C. Kauai. 

 Form A. South Molokai. 



Form A. South Molokai. 

 Form B. Kauai. 



Erylus caliculatus Lendenfeld. 

 Figures 6-10, 24, 25, 29. 



I- 7. — Apical views of triaene-cladomes; magnified 100; phot. Zeiss, apochr. 16, compens, oc. 6: 



1, 3, of Erylus rotundus var. typica from nortlieast Hawaii (form D) ; 



2, 4, of a dark specimen of Erylus rotundus var. typica from Kauai (form B) ; 



5, of Erylut rotundus var. cidaris; 



6, 7, of Erylus caliculatus. 



8-10. — Side views of triaenes of Erylus caliculatus; magnified 100; phot. Zeiss, apochr. 16, compens. 

 oc. 6. 



II- 15. — Amphioxcs of Erylus rotundus var. typica; magnified 100; photo. Zeiss, apochr. 10, compens. 



oc. 6: 



11-13, of a specimen from northeast Hawaii (form D); 

 14, 15, of a light specimen from Kauai (form C). 

 16, 17. — Groups of megascleres from spicule-preparations of Erylus rotundus var. typica; magnified 

 100; phot. Zeiss, apochr. 16, compens. oc. 0: 



16, of a specimen from South Molokai (form A) ; 



17, of a dark specimen from Kauai (form B) ; 



a, sharp-pointed amphioxes; b, blunt amphiox (amphistrongyle) ; c, style. 

 18-23. — Rhabd megascleres of Erylus rotundus var. megarhabda; magnified 100; phot. Zeiss, apochr. 

 16, compens. oc. 6: 



18, an amphistrongyle of a specimen from South Molokai (form A) ; 

 19-22, amphioxes of a specimen from South Molokai (form A) ; 



23, an amphiox of a specimen from Kauai (form B). 



24-28. — Groups of spicules from spicule-preparations; magnified 100; phot. Zeiss, apochr. 16, com- 

 pens. oc. 6: 



24, 25, of Eiylus caliculatus; 



26-28, of Erylus rotundus var. cidaris; 

 a, (Figs. 24-28) amphioxes; 



c, (Fig. 24) style; 



d, (Fig. 26) triaene; 



e, (Fig. 27) microrhabd; 



f, (Figs. 24, 27, 28) aspidasters; 



g, (Figs. 24, 27) acanthtylasters. 



29-32. — Views of whole specimens; phot. Zeiss, anastig. 480/412 mm.: 



29, Erylus caliculatus; natural size; 



30, Erylus rotundus var. typica from South Molokai (form A); magnified 1: 1.08. 



31, Erylus rotundus var. cidaris; magnified 1: 1.13; 



32, Erylus rotundus var. megarhabda from South Molokai (form A); magnified 1: 1.08. ; 



