WEIGHT ON THE AXOLOTL. 61 



cally refused to believe in the existence of a persistent larval form 

 among the Amphibia. I think, however, it is more than probable that 

 Cuvier's memoir on "Doubtful lleptiles," published in Humboldt's Ke- 

 cueil d'Observations de Zoologie,* was seen by Rusconi, or at least heard 

 of by him, as it was read before the French Institute, as early as Janu- 

 ary, 1807 ; and this great anatomist insists so strongly on axolotl being 

 a larval condition of some salamander, and saw so many things in its 

 anatomy that he says strengthened him in this opinion, that it is really 

 no wonder the Italian salamander- observer, feeling himself so strongly 

 supported, indulged in a rather contemptuous laugh at our great Eng- 

 lish anatomist. Cuvier's account of the visceral anatomy is so short, 

 that we venture to subjoin it here; it will be found at page 109 of the 

 work referred to, and is illustrated with several plates. With the greatest 

 deference to the memory of one of the greatest of modern anatomists, 

 and the author of the "Memoirs of the Mollusca," a work which exhibits 

 a wonderful skill in minute dissection, yet I have never met with an ana- 

 tomical description which seems so decidedly written to prove a foregone 

 conclusion. Cuvier thought axolotl a larval form ; through the kindness 

 of Humboldt, he was given specimens, from the anatomy of which much 

 was to be proven ; and yet we read such statements as that the " spleen 

 is very small, and in the middle of the mesentery ;" that the " oviducts 

 were so very delicate, that one could perceive them with difficulty j" with 

 what justice these facts, tending to prove an immaturity of condition, 

 are stated, will be seen a little further on :— 



" In axolotl," writes Cuvier, " tbe oesophagus is short, plicated longitudinally, and is 

 continuous with the stomach; this latter is large, membranous; the forepart is a little 

 plumpish, but towards tbe pyloric orifice, it is much contracted. I found it full in the 

 two specimens (examined) of small fresh-water Crustacea, strongly resembling our native 

 ones. The animals had swallowed these without masticating them ; and their legs were 

 found undigested down as far as the rectum. 



"The intestinal tract is tolerably large; more especially the portion nearest the liver, 

 and tolerably long ; it consists of two principal loops, and is furnished neither with a 

 ccecum nor internal valve of any kind. 



"The liver is rectangular, and without any deep lobes. I could not detect the pre- 

 sence of a gall-bladder. 



" The spleen is very small, and is placed in the middle of the mesentery ; this latter 

 is as we find it in the ordinary salamanders. Indeed, all the intestines are just those of 

 a salamander. 



" The ovaries are very small, flabby, and contained hardly a trace of ova3. They 

 occupied the same place, and are furnished with the same greasy appendages that are 

 found in the common salamanders. Again, the oviducts are so delicate (si freles) that 

 one can scarce perceive them. 



"From all these marks of immaturity, and that intimate resemblance which all the 

 viscera bear to those of the salamander and their larva, I conclude that the Mexican 

 axolotl is but the larva of some huge salamander, perhaps the same that is alluded to 

 by Micbaux." 



* " Recueil d'Observations de Zoologie et d'Anatomie comparee faites dans l'Ocean 

 Atlantique, dans l'interieur du Nouveau Continent et dans la Mer du Sud, pendant 1799, 

 1803." Par Al. de Humboldt et A. Bonpland. l er volume. 1811. 



