484 
were all injected. Further, the skin and the liver were well filled in 
places, and the medium had passed into the cardiac aorta, the gills 
and the dorsal aorta. 2. The caudal vein and its factors and the 
posterior cardinals (but not the segmental veins) were filled, but the 
external surface only of the gut was injected as a beautiful network. 
There was not much in the portal vein, and nothing in the liver, the 
heart and arteries, or in any part anterior to the heart. In this 
preparation was demonstrated the irregular double longitudinal sinus 
situated dorsal to the aorta with its double pairs of segmental vessels. 
3. The caudal heart and vein, the posterior cardinals and a few seg- 
- mental veins, the gut, portal vein and hepatic veins, the peribranchial 
and associated sinuses, the inferior jugular vein, the heart, afferent 
branchial arteries and gills, and also the dorsal aorta behind the gill 
region, both anterior cardinals and the cranial sinuses were all injected. 
The paired abdominal sub-chordal sinuses with their segmental vessels 
wereempty. 4. Caudal heartand vein were well filled, but the posterior 
cardinals were empty except anteriorly. There was nothing in the 
portal vein or the gut, but a little colour was showing in the portal 
heart and its branches to the liver, and a very little in the liver 
itself. The abdominal sub-chordal sinuses and their segmentals were 
injected here and there. There was a little in the peribranchial sinuses 
and the associated ventral sinus, but the ventricular sinus was well 
filled. Nothing was found in the heart or the arteries. The inferior 
jugular was empty, but in the gill region, and for a short distance in 
front, the sinus dorsal to the gut was well filled, and a little had 
penetrated into the sinuses of the head. 
RatHKs in 1825 first etablished a lacunar connection between the 
arteries and veins of a vertebrate, his material being the sexual organs 
of the Lamprey. The discovery of another such connection in Myxine 
was announced in 1890 by KLincKowsTtrön, who held that the sub- 
cutaneous spaces of Myxine were to be regarded a blood spaces rather 
than as lymphatics. In the same year G. Rerzius, by his discovery 
of the caudal hearts, demonstrated one method by which the so-called 
lymphatics and veins were connected up. In an unpublished manuscript, 
kindly placed at my disposal by Baron Kiinckowstr6ém, it is stated 
that the true segmental blood vessels are accompanied by paired 
lymph vessels, which open into a subcutaneous lymph network in the 
region of the slime glands. I also find these paired vessels. The 
sub-chordal lymph sac is asserted to be in open communication with 
