11. For the trachea is very long, and the œsophagus still longer, and the commencement of the trachea is close to the mouth, so that the tongue appears to lie beneath it. The trachea appears to be above the tongue because this last can be retracted, and is not always in one position, as in other animals. Their tongue is long, thin, and black, and can be put forth for some distance. The tongue of serpents and saurians is distinct from that of all other animals, for the extremity of the tongue is cloven; this is most remarkable in serpents, for the extremities of their tongues are like hairs. The seal also has a forked tongue. The serpent has a stomach like a very wide entrail, like that of the dog, afterwards a very long and thin intestine, which is alike to its extremity. 12. Behind the pharynx is a small kidney-shaped heart, so that at times the apex does not appear to be directed towards the chest, next to this is a single lung, divided by a muscular passage, very long, and descending a long distance from the breast. The liver is long and simple, the spleen small and round, like that of the saurians. The gall resembles that of fish, in water serpents it is situated on the liver, in others generally upon the intestines. They all have pointed teeth, and as many ribs as there are days in the month, for they have thirty. Some persons say that in one respect serpents resemble the young of the swallow, for if their eyes are pierced with a pointed instrument, they will grow again, and if the tails of serpents or lizards be cut off, they will be reproduced. 13. The same remarks will apply to the intestines and stomachs of fishes, for they have one simple stomach, but it differs in form, for in some fishes it is like a bowel, as in the one called scarus, and this is the only fish that appears to ruminate, and the size of the intestines is simple and folded together, for it can be resolved into one, by unfolding it. The appendages of the stomach appear to be peculiar to fishes and birds, for birds have them above the stomach, and few in number, but in fish they are above, and around the stomach. Some have many appendages, as the gobius,[74] galeus,[75] perca, scorpios,[76] citharus,[77] trigla,[78] and sparus.[79] But the cestreus has many on one side of the stomach, and only one on the other. Some have only a few, as the hepatus[80] and the glaucus,[81] and the chrysophrys[82] also has only a few, but some individuals differ from others, for one chrysophrys has many, another has only a few. There are some fish which have none of them, as most of the cartilaginous genera; others have a few, and some a great many, and all fish have these appendages very near the stomach itself. [74] Gobio, gudgeon. [75] Shark. [76] Cottus scorpius. [77] Probably Pleuronectes rhombus. [78] Mullus surmulentus. [79] Sparus maina. [80] Theutis hepatus. [81] Probably Gobio gozo. [82] Sparus aurata.