Besides I believe that in no case are the absorbents as much distended during life by serum, as they are by mercury from injections. When these have succeeded well, we see upon many parts a net-work of very evident vessels. On the contrary, most commonly nothing similar is to be seen in living animals. With whatever promptness we examine most of the surfaces which the serous membranes cover, surfaces that can be laid bare without making the blood flow, nothing is seen, except sometimes small transparent striæ, which soon disappear. Now it is impossible that if the absorbents were as full during life, as they are by injections, but what their transparency contrasted with the colour of the surrounding parts, would render them evident. I have selected however very large dogs, to try to see their course better. I believe that injections double at least the diameter of these vessels. _Of the Capacity of the Absorbents in their course._ The capacity of the absorbents is remarkably variable; it depends entirely, in the dead body, on the state in which these vessels were in the last moments. In subjects of the same stature and age, they are sometimes very apparent, at others hardly visible. They are double, treble even, in some dropsical patients, what they are in a natural state. Many authors say that they have seen branches almost equal to the thoracic duct, and larger than the trunk of the right side. To be convinced of the extreme variety of the absorbents, without the assistance of injections, take the lymphatic glands in different places, then dissect carefully the parts in the neighbourhood; you will easily find all the absorbents that go to them. Then you will be able to satisfy yourself of the extreme variety of their size; we can even in this way trace them far enough without injection. Sometimes in order to find the end of the thoracic duct, I take a gland in the neighbourhood of the second lumbar vertebra; thus following the empty lymphatic tubes that go from it towards the canal, I find it without difficulty. When we are not in the habit of finding immediately the absorbents, this method of searching for them by means of the glands, which are always very evident, infallibly succeeds; it cannot be used it is true in the extremities; but in the thorax and especially in the abdomen, it is very convenient. For example, by taking the inguinal glands we can trace these vessels to the thoracic duct, by injecting them, or even without. Some authors have advised making an opening in the gland and placing a tube in it; this rarely succeeds; it is much better to open the vessels that go from the gland, at the place where they go off.