18 
to it a reticulated appearance, especially upon the 
superior ends of the lungs. But these organs exhibit 
nothing of that cellular or parietal structure, which 
so remarkably characterizes the lungs of the common 
Salamandra, those of the family of Ranae, or Frogs, 
the Crotali, or Rattlesnakes, and many other ani- 
mals. 
In their form, as well as in their texture, we find a 
very striking resemblance between the lungs of the 
Siren and those of the Lacerta lacustris.^ In the 
Siren, indeed, they are more uniformly of oife diame- 
ter, through their whole length, than they are in the 
Water- Lizard. But, even in the American animal, 
the lungs are not, as Dr. Schreibers asserts, ^‘^through- 
out equally wide;’’ and at their lower and loose ends, 
they are gradually attenuated, and terminate in a 
very narrow point. 
From this unfinished, but I flatter myself correct, 
description of the lungs of the Siren, it must appear 
sufiicieutly evident, that these organs, though they 
greatly resemble those of some species of lacerta, are 
very unlike the lungs of the lacerta salamandra. 
Nor are they much more nearly allied to the lungs 
of the Proteus anguinus of Laiirenti. For in this 
latter animal, as appears from the drawings and de- 
scription of the ingenious Dr. Schreibers, the lungs, 
on each side, are composed, principally, of a long 
* I beg leave, in this place, to quote the description which Ol. 
Jacobsens has given of the lungs of this little animal: “Duo oblongi 
sacculi aeri recipiendo dicati, pulmones const! tuunt, qui valde ni - 
tidi ac pellucentes ab initio oesophagi ductum alimentorura comi- 
tantnr et ad ovaria usque protenduntur. Vasa sang'uinea secundum 
longitudinem pulmonum cum rarnis suis minutissimis decurrunt.” 
