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. [Illustration] G. Liljevall del. Ljustryck af Chr. Westphal Stockholm. * * * * * Transcriber Note Minor Typos were corrected. Inconsistencies in capitalization and abbreviations were left as printed.