110 Observations on the Natural History 
to speak with confidence : on this and some other points they 
were unable to satisfy their curiosity, having sacrificed all the 
protei which they possessed to other researches. 
The reader perhaps may expect, that after having thus set 
aside the common opinion, that the two ait-bladders of the pro- 
teus perform the function of lungs, we should declare the pur- 
pose they are designed to serve. This, however, say the au- 
thors, it is difficult to do, as it is to say what is the true and 
primary use which the air-bladder serves in fishes ; but this 
point, at a future period, they hope to be able to investigate, 
both in the protei and in fishes. 
Such is a condensed account of the labours of Professors 
Configliachi and Rusconi, regarding the history and structure of 
this singular animal. Those who may desire more minute in- 
formation, must consult the work itself, and more particularly 
the numerous and beautiful figures, designed by Dr Rusconi, 
and engraved by Anderlpni, with which the work is adorned. 
D. E. 
Explanation of Plates. 
Plate VI. Fig. 1. View of the head from below, eight times 
greater than natural, a a, the two branches of the lower jaw ; 
bb , processes of the temporal bones to which they unite; c , 
the roof of the palate ; d, the os hyoides ; eee , the three bran- 
chial arches of the right side ; fg, the intermediate bones of 
the first and second arches ; hhh , the three first vertebrae ; 
nn, the branches of the os hyoides. 
Plate VI. Fig. 2. The skeleton of the proteus of its natural 
size ; a , the three cartilages, forming the shoulder ; b, the 
pelvis. 
Plate VI. Fig. 3. The lower half of the trunk of a female pro- 
teus laid open. a, the alimentary canal shortened and 
straitened from the action of ardent spirits : — at its termina- 
tion, it is slit up to shew the common focus of the ureters 
and oviducts, into which two bristles are inserted, the open- 
ing from the urinary-bladder is indicated by a single 
i 2 
