Pl. VI.

Phacops macrophthalmus Burm. p. 65

Fig. 1. Horizontal section of the cephalic eye 30/1. » 2. A similar one near the inferior margin, a cheek 30/1. » 3. Vertical section of a cephalic eye 30/1. » 4. A similar, twice as much enlarged 60/1. » 5. Also a similar, a cheek 30/1. » 6. Hypostoma 2/1. Spec. EA. » 7. The wings of the hypostoma, seen without foreshortening 4/1. EA. » 8. The diminutive right macula 12/1, surrounded by incoherent terrace lines. » 9. The left macula 12/1. Specimens from Gerolstein Eifel, Devon.

Acaste sp.? p. 51.

Fig. 10. The hypostoma 8/1. From Mulde, Fröjel, Gotland.

Phaëtonides Stokesi Murch. p. 66.

Fig. 11. Hypostoma 4/1. Gotland, Eksta, Djupvik.

Phillipsia sp. p. 66.

Fig. 12. A portion of the cephalic eye 20/1. » 13. The hypostoma 4/1. » 14. The right macula 12/1. Specimen from Beeren Eiland, Oswalds förberg, communicated by Hr. J. G. Andersson.

Phillipsia sp.? p. 66.

Fig. 16. The hypostoma 3/1. » 16. The right macula 12/1. » 17. Horizontal section of the cephalic eye 60/1. » 18. Vertical section of the cephalic eye, a cheek 60/1. Probably from the Carbon of Belgium.

Proetus concinnus Dalm. p. 67.

Fig. 19. Horizontal section of the cephalic eye, a little oblique, at right the innermost stratum with the rock 60/1. » 20. Vertical section of the cephalic eye. The diameter of the prisms 0,03 millim. » 21. Hypostoma 4/1. » 22. The right macula 12/1. » 23. The same with a light, transparent spot 12/1. Specimen from Djupvik, Eksta.

Proetus conspersus Ang. p. 68.

Fig. 24. A portion of the cephalic eye 20/1. » 25. The hypostoma. Cast of the interior side 4/1. » 26. Cast of the interior side of the left macula 12/1. Fig. 24 from Öja, Gotland, the others from Kräklingbo.

Proetus signatus Ldm. p. 68.

Fig. 27. Hypostoma 4/1. » 28-30. Three pair of maculæ with dark ocelli in a white spot.

Ptychopyge angustifrons Dalm. p. 69.

Fig. 31. Horizontal section of the cephalic eye 250/1. » 32. Hypostoma, a broad variety 1/1. » 33. Another, a narrow variety 1/1. » 34. The left macula of the hypostoma fig. 32 4/1. » 35. A similar of the narrow variety 4/1. » 36. Vertical section of a macula. a the macula 20/1. Specimens from Vestanå and Kungs Norrby, Östergötland.

Ptychopyge cincta Brögger p. 69

(according to Fr. Schmidt. The figure 12 a of Brögger resembles, however, the hypostoma of Pt. angustifrons, but not the hypostomata which have been prepared from the Ptych. cincta).

Fig. 37. A hypostoma; the maculæ are directed obliquely 2/1. » 38. The right macula of another specimen 4/1. » 39. Vertical section of a macula 60/1. Specimens from Kungs Norrby, Östergötland.

Ptychopyge aciculata Ang. p. 68.

(Compare Brögger II Taf. I, fig. 13.)

Fig. 40. The hypostoma, cast of the interior surface 1/1. » 41. Cast of the right macula 4/1. Specimen from Öland, Brunsby.

Ptychopyge glabrata Ang. p. 69.

Fig. 42. Original of Brögger's fig. 14. Cast of the inside of the right macula 4/1. Ǎlleberg.

Elyx laticeps Ang. p. 19.

Fig. 43. The interior surface of the right fixed cheek and the glabella. Magnified. Specimen from Andrarum. 4/1.

Conocoryphe p. 19.

Fig. 44. Cast of the interior surface of the left cheek. Magnified. From Andrarum. 4/1.

Solenopleura brachymetopa Angel. p. 19.

Fig. 45. The head shield, cast of the interior surface. Magnified. Specimen from Andrarum, Scania. 4/1.

Apus cancriformis Schäffer p. 73.

Fig. 46. The hypostoma from the outside 8/1. » 47. The same from the inside 8/1. » 48. A side view of the same, 8/1. a the duplicature of the head shield, b posterior integument of the hypostoma, c the ventricle, d the mouth. » 49. The right white spot at the posterior margin of the hypostoma, seen from the outside in transmitted light 150/1.

K. Sv. Vet. Akad. Handl., Bd 34, No 8. Lindström: Trilobites. Pl. VI.

Click on image to view larger sized.

G. Liljevall del. Ljustryck af Chr. Westphal Stockholm.