500 BULLETIN 34, UNITED STATES NATIONAL MUSEUM. 



PLATE XXI. 



Amblystoma sp., viscera, drawn by Prof. S. F. Baird. 



Fig. 1. Amblystoma punctatum, viscera, natural size, female; the digestive and uro- 

 genital systems drawn separately ; lettering as before ; cl, cloaca ; June, 1848. 



2. Amblystoma punctatum, urogenital system of male, enlarged; lettering as 



before ; May, 1849. 



3. ^m?)?^s?om« ojjacitm Grav., male, cloaca; 1, vas deferens ; 2, ureter; 3, groove 



from each vas deferens, which unites with its fellow at apes of peninsula 

 (9), and is continued as a branch on each side, dividing and inclosing the 

 process (4), and, reuniting, passes round the posterior part of the folds of 

 membrane (5) ; 4, oval, fleshy bodies, supported on short stems equal to 

 themselves ; 5, a series of deep folds of membrane of each side, nearly meet- 

 ing inferiorly; 6, slight protuberance in the depression between the folds; 

 7, folds which arise between the bodies (4) as one, and, bifurcating, sink 

 away behind the folds (5); 8, a second set of folds anterior to 7. 



4. Amblystoma opacmn, liver from above; a, from below. 



5. Heart and branchial vessels of Siren lacertina, diagrammatic; a, transverse 



section of bulbiis arteriosus. 



PLATE XXII. 



Chondrotus tenebrosus, skeleton of larva, from above, natural size. Fig. 1, stull from 

 below ; 2, lower jaw and hyoid arches from above. From Salem, Oregon. 



PLATE XXIII. 



Chondrotus tenebrosus, larva, natural size, from below. 



PLATE XXIV. 



Hyoid apparatus of Ambhjstomidcv ; Figs. 1, 2, and 3 dissected and drawn by Dr. E. E. 

 Gait; the remainder by E. D. Cope. 



Fig. L Chondrotus tenebrosus, from below : |. 



2. Chondrotus tenebrosus, larva, from above ; X 2. 



3. Chondrotus tenebrosus, larva, from below ; X 2. 



4. Chondrotus aterrimus, from below ; f . 



5. Chondrotus aterrimus, from above ; f . 



6. Chondrotus paroticus, from below, |. 



7. Chondrotus paroticus, fvom above; f. 



8. CJiondrotns decor ticfdus, {rom below; |. 



9. Chondrotus decorticatus, tvom aboxe; f. 



10. Lingucelapsiis annulatus, from below; f. 



11. Lingucelapsiis annulatus, from above; \. 



12. Linguwlapsus lepturus, from above; f. 



13. Lingucelapsiis lepturus, from below ; f . 



PLATE XXV. 



Hyoid apparatus of Amblystomidce and Hynobiidce ; Figs. 1, 2, 8, and 9 dissected 

 drawn by E. D. Cope ; 3-7 by E. E. Gait, and 10, 11 from R. Wiedersheim. 



Fig. 1. Chondrotus microstomus, ixonxbelo-w; X 4. 



2. Chondrotus microstonius, from above ; X 4. ~ 



3. Chondrotus tenebrosus, larva, side view ; X 2. 



