At the conclusion of my observations on the alimentary canal of the axolotl, I received a copy of Professor Luigi Calori's paper, entitled "Sulla Anatomia dell' Axolotl," published in the memoirs of the Academy of Science, Bologna.[1] This elaborate paper leaves but little to be said in addition on the anatomy of this animal; and yet, perhaps, the publications of this Academy—highly valuable though they be—maybe as little accessible in Britain as those of our own Royal Society appear to be in Italy. Were the latter otherwise, Dr. Calori would have known of the paper of Sir Everard Home, referred to by us, "On the Reproductive Organs of Axolotl," and not have claimed priority for his discovery and very careful details of these same structures, so unaccountably passed over by Cuvier. This thought, and the fact that, though Dr. Calori's paper is illustrated with five plates, not one represents the viscera in situ—nor is there a correct representation of the spleen, or of the gall-bladder—makes us not hesitate to give the result, as detailed in the previous paper, of the dissections of two fine specimens, male and female, of the axolotl (for which we are indebted to the kindness of Dr. Dickie, late Professor of Natural History, Queen's College, Belfast, now of Botany, at Aberdeen); while, in justice to the important paper in the Bologna memoirs, we now append a brief abstract of the portions that more especially treat of the alimentary tract. The osseous and blood system are equally painstakingly investigated; but for these we will refer to the work itself:—
"The interior of the stomach is lined with a dry scaly epidermoidal-like stratum, which is also met with in the pharynx and œsophagus,—a net-like structure, with wide meshes, occurs, seemingly depending from the blood-vessels. In these meshes are a large number of small, regularly disposed cells, probably a smaller vascular net-work, not easily perceived without the assistance of high powers. Within the meshes of this smaller net, the (mucous) glands of the stomach open,—they are very numerous, tubular, and quite microscopic.[2]
"The muscular coating of the stomach is rather thin, composed of longitudinal fibres, and is continuous with the muscular coats of the oesophagus, and likewise of the intestinal tract. The transverse fibres are more abundant towards the pyloric orifice, and here the coats of the intestine are somewhat thicker; there is no lack of an intermediate cellular membrane between the muscular and mucous coats, but it is very thin.
"The serous investment is very thin, and, having enveloped both sides of the stomach, it is prolonged into two folds: one, the right and lower, going to the liver, forms the gastro-hepatic ligament: the other, the left and higher, goes to the spleen, not placed as Cuvier thinks, in the centre of the mesentery, but against the left side of the stomach.
"The œsophageal orifice is larger than the pyloric one; this latter is very narrow, is slightly twisted, and a series of folds in the lining membrane almost completely closes it. These folds are prolonged into the first portion of the small intestine. These folds in the pyloric orifice take the place of a valve; it is externally marked by a constriction, inferior to which the duodenum commences; this is at first very narrow, and descends in- ↑ Memoire dell' Accademia delle Scienze dell' Instituto di Bologna. Tomo iii. 1851, pp. 269–361.
- ↑ It will be seen by reference to our remarks on the internal structure of the stomach, that Dr. Calori has not rightly comprehended this portion, but his specimen was a very young one: contrast his fig. 9, plate XXIII., with ours, fig. 4. plate II. The general outline of this viscus is likewise very much exagerated in fig. 8a, x., Plate XXIII., of Calori.
