Fig. 6. Distal portions of grasping spines of Recent Sagitta (A–C, G) and Cambrian Phakelodus (D–F). A. Three spines of the same grasping apparatus showing irregularity of the anterior margin of outer layer and fibrous structure of the tips, note that tip of A2 is much more strongly curved than those of A1; ZPAL C.IV/6.16. B. Specimen treated shortly with KOH solution, in result the fibrils of tip are slightly disintegrated; ZPAL C.IV/ 4.7 C. Specimen treated longer with KOH solution, the outer layer not preserved, fibrils of the middle layer continue up to the tip where they are strongly disintegrated; ZPAL C/100.14. D–F. Specimens with tips looking differently from rest of the spines (the spine illustrated in F belongs to the natural assemblage illustrated in Fig. 7L). D, F. Subsurface Upper Cambrian of northern Poland; ZPAL C.IV/1.6; ZPAL C.IV/108.4 respectively. E. Upper Cambrian, Trolmen quarry, Kinnekulle, Sweden; SMNH X3519, 95.17. G1. Anterior portion of a head in ventral view, note that distal portion of one of the spines is broken off and accidentally attached to other spines. G2. Magnification of the fragment pointed by arrow in G1, note comparatively small pulp cavity, thickinner layer and well developed insertions connecting the inner and outer layer, the middle layer preserved fragmentarily, structure of the tip not well visible; ZPAL C.IV/2.15. Abbreviations: il, inner layer; ml, middle layer; ol, outer layer.

Published as part of Szaniawski, Hubert, 2002, New evidence for the protoconodont origin of chaetognaths, pp. 405-419 in Acta Palaeontologica Polonica 47 (3) on page 411, DOI: 10.5281/zenodo.13304956