ClipArt ETC
"Restored skeleton of Palaeospondylus gunni. d.c., Cirri of dorsal margin; l.c., long lateral cirri; v.c., cirri of ventral margin; n., nasal ring; t.p., anterior trabeculo-palatine part of cranium; b., anterior depression or fenestra; c., posterior depression or fenestra; a., lobe divided off from anterior part; p.a., posterior or parachordal part of cranium; x., post-occipital plates." -Thomson, 1916

Palaeospondylus Gunni

"Restored skeleton of Palaeospondylus gunni. d.c., Cirri of dorsal margin; l.c., long lateral cirri;…