A treatise on zoology . Fig. 175. Ccphalasjns Lyelli, Ag. ; restoration of dorsal shield. (After Lankester, from A. S. Wood-ward.) , antorbital fossa ; , antorbital prominences ; , interorbital groove ; ), inter-orbital plate; , marginal cells; , orbital rim; , posterior angle; , posteriorcornu ; , postorbital depression ; , posterior ridge ; j).s, posterior spine ; r, Fio. ITC. Trcmatafpis SclnniiJti, Rohon, enlarged. A, ventral, and B, dorsal view of the shields.(After Patten.) cim, anterior area with polygonal plates ; , anterior median opening ; d.
A treatise on zoology . Fig. 175. Ccphalasjns Lyelli, Ag. ; restoration of dorsal shield. (After Lankester, from A. S. Wood-ward.) , antorbital fossa ; , antorbital prominences ; , interorbital groove ; ), inter-orbital plate; , marginal cells; , orbital rim; , posterior angle; , posteriorcornu ; , postorbital depression ; , posterior ridge ; j).s, posterior spine ; r, Fio. ITC. Trcmatafpis SclnniiJti, Rohon, enlarged. A, ventral, and B, dorsal view of the shields.(After Patten.) cim, anterior area with polygonal plates ; , anterior median opening ; ,dorsal shield ; , pits of lateral line ; m, mouth ; », median area with plates ; or, orbit; ,posterior area witli plates ; , lateral opening; , ventral openings, probably branchial;, ventral plates ; !, ventral shield. CEPHALASPIDOMORPHI 203 the Cephalaspidae. Small scales like those of Thelodus are alsopresent in certain regions. In the Cephalaspidae the scales also extend on to the fins,forming linear series closely resembling the lepidotrichia of Teleo-stome fish; and a ridge of strong scales is present along the back,and along the sides of the trunk, which thus ac(|uires a triangularsection (Fig. 174). The tail of the Tremataspidae is unknown, andmay have been naked. The expanded anterior region in the Atele-aspidae is covered wdth a flexible armour of small polygonal
Size: 1947px × 1283px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublishe, booksubjectzoology
