File:Montgomery Plethodon cinereus larva.jpg

English: Plethodon cinereus

Fig. 1 shows a larva freed from its envelopes before killing so that it had straightened out; and fig. 2, an older larva, similarly treated, but which had still retained much of its normal position. In fig. 3 is shown a camera drawing of a section through a stage somewhat younger than that of fig. 1.

Fig 3: The mouth (Mo.) leads through the pharynx (PA.) and oesophagus (OEs.) to the stomach (St.), and posteriorly to the latter is a short diverticulum (D.). The small intestine (Int.) is seen to be tubular in its proximal portion, but more distally to pass over into the wall of the yolk-mass (Yk.)

Fig. 4 and 5, dorsal portions of cross -sections of the larva shown in its entirety in fig. 1. Int., intestine; Yk., yolk; M. T., metanephroi; V.C., cartilaginous vertebral arches; N.C., notochord; So.A.L somatic mesoderm; S.D. segmental ducts; C. coelom; M., median mesenteries; L., liver; Ect., ectoderm; G.R. genital ridges; So.M., somatic mesoderm; Sp.M., sphlanchinic mesoderm;