THE BATRACHIA OF NORTH AMERICA. 499 



PLATE XIV. 



Skeleton of AmMystoma jyunctatum, one-half natural size; superior view. No. 722. 



PLATE XV. 



AmNysioma panctatum, skeleton from below; natural size. 



PLATE XVI. 



Amhlystomapunctatum, skull, one-half larger than natural size. 



Fig. 1. Skull, above. 



2. Skull, below. 



3. Skull, left sidCj exterior. 



4. Skull, left side, interior. The numbers below are those of the nerves which 



issue from the foramina of the tigure. 



PLATE XVII. 



Visceral anatomy oi Amhlystoma liunctatum, from drawings by Prof. S. F. Baird. 



Fig. 1. Viscera in place, from below. 



2. Liver, from above ; a, from below, 



3. Corpora adiposa and ovaries ; one outlined only. 



4. Laryns, lungs, stomach, and spleen isolated. 



PLATE XVIII. 



Amblystoma imnctatum, development of larva, from drawings by Prof. S. F. Baird, 



magnified four diameters. 



Fig. 1. Embryo taken from egg 4 lines in diameter, x 4. 



2. Another embryo, from above; a from below. 



3. Larva just from the egg, from below, x 8. 



4. Larva two weeks free from egg, with three digits on manus, from above ; 



a, from side; X 4; May, 11, 1848. 



5. Larger larva, with posterior limbs, from above, X 4. "In sis individuals, 



all had the right branchiae less developed than the left;" note S. F. Baird. 



6. Hind limb before development of digits. 



7. Right fore-foot, from above, of specimen older than fig. 4 ; 5-25, 1848. 



8. Eye of fig. 4, showing lens. 



PLATE XIX. 



Amblystoma opacum and Pletliodon erythronoUis, skulls, twice natural size. 



Fig. 1-3. Amblystoma opacum. 

 4-6. Plethodon erythronotus. 



PLATE XX. 



Anatomy of Amblystoma opacum, drawn by Prof. S. F. Baird. 



Fig. 1. Viscera in place, from below ; lettering as before ; female ; natural size. 



2. Oviducts and fat bodies; natural size; cl, cloaca; fo, fontanelle of oviduct; 



k, kidney. 



3. Stomach and liver; the latter everted, to show portal vessels. 



4. Cloaca much enlarged, showing mouths of oviducts and labia {la.'). 



5. Urinary bladder distended. 



6. Urogenital system; C A, corpus adiposum ; T, testis; h, kidney; vet, vasa 



efferentia testis ; refc. vasa efiferentia, reuis ; v. d. vas deferens. 



