406 The Vascular Supply of the Pleura Pulmonalis 
Dogiel demonstrated a plexus of blood-vessels about the lymphatics in 
the ear and hind leg of the rat and in the mesentery of the rat, the cat, 
and the dog. In his second contribution he described a plexus about the 
lymphatics of the capsule of the kidney in the dog. 
Arnstein, in a foot-note to the earlier of Dogiel’s contributions, re- | 
marked on the fact that the blood vascular network was external to the 
lymphatics and supported the opinion advanced by Dogiel that they, in 
some way, assisted in the circulation of the lymph. In a supplementary 
note to Dogiel’s second paper, Arnstein considers Dogiel mistaken in 
calling the network in the capsule of the dog’s kidney perilymphatice. 
When the lymphatics are collapsed they lose their beaded appearance 
and it is quite difficult to distinguish their valves; many run for some 
distance in practically a straight course, conditions which were noted by 
Hewson (5). 
In making injections of the lymphatics of the pleura of the horse and 
of man it has frequently happened to me that the injection mass would 
fail to enter any lateral branches and, for a distance of fifty or sixty milli- 
meters, there would be a straight trunk (Fig. 12), which eventually broke 
out into a complete network of lymphatics. It would be erroneous to say 
that there were no other lymphatics in the area through which this single 
trunk passed, for under a dissecting lens they could readily be made out. 
When the lymphatics are collapsed there is often an appreciable distance 
between the encircling network of blood-vessels and the lymphatics; but, 
when the lymphatics are distended, the network of blood-vessels is in close 
contact. The former conditions are indicated in Fig. 9, the latter, in Fig. 
3. Dybkowsky (3) has noted a similar relation in his study of the 
lymphatics of the pleura costalis. 
Nore.—After the manuscript for the above article had left the author’s 
hand, H. M. Evans (3*) published the results of his investigations on the 
vasa vasorum of lymphatics. The author regrets that it appeared too late 
to be noted in the review of the literature, since it is the most complete work 
on the subject that has thus far been published. 
BIBLIOGRAPHY. 
1. CRUIKSHANK, W.—The Anatomy of the Absorbing Vessels of the Human 
Body. London, 1790. 
2. DoctrLt, A.—Ueber ein die Lymphgefaésse unspinnendes Netz von Blut- 
capillarien. Archiv f. mikros. Anat., Bd. 17, 1880. (a) Ueber 
die Beziehungen zwischen Blut-und Lymphgefassen. Archiv 
mikros. Anat., Bd. 22, 1883. 
