. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. 224 Dr. A. Giiuther on Ceratodus, sistent, tlie lateral brandies being either entirely absent (as in the former), or quite rudimentary (as in the latter). In all these cases the analogy of this structure to the diphyoccrcy of the terminal portion of the tail is apparent, whilst a hetcrocercal condition is rei)resentcd in the pectoral fin of Acipenser. In this fish the axis {h) is not inserted in the longitudinal median. Ceratodus. Acipcnser. rt, cai'pal cartilage ; fc, jointed
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. 224 Dr. A. Giiuther on Ceratodus, sistent, tlie lateral brandies being either entirely absent (as in the former), or quite rudimentary (as in the latter). In all these cases the analogy of this structure to the diphyoccrcy of the terminal portion of the tail is apparent, whilst a hetcrocercal condition is rei)resentcd in the pectoral fin of Acipenser. In this fish the axis {h) is not inserted in the longitudinal median. Ceratodus. Acipcnser. rt, cai'pal cartilage ; fc, jointed axis; c, branches having- the carpus as base ; (7, branches liaving tlie axis as base. line of the carpus (a), but quite at the inner corner; conse- quently brandies exist on one side of the axis only, viz. on that side on which they are needed for the support of the fin- rays. The axis is comparatively sliort and feeble, composed of three joints, and forming the base for three branches [d). Three other branches (c) are inserted immediately into the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original London, Taylor and Francis, Ltd
Size: 1218px × 2052px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookce, booksubjectbotany, booksubjectgeology, booksubjectzoology
