EE ty a eet Se i ge | 
es 
1922.] * Renal Portal’’ System 155 
sense that lymph is separated from the blood in os ee nate 
— the term “ re-absorption”’ has not the sam ng i 
twocases. On the Tubule cum Rete theory, Skee is no more re- 
absorption i in the kidney (in the neo- Ludwig sense ) than there 
is in the salivary gland. Further we may well enquire from 
supporters of the neo-Ludwig view in what way they suppose 
glomerular filtration and tubule absorption per se to be superior 
to the more simple, or at least more usual, process found in all 
other glands? Nobody will deny that glands in general can 
(and do) abstract as much water and crystalloid substance from 
the blood as the kidney does, or that the ordinary type of gland 
could, if the organism required it, concentrate urea, sulphate 
other substances to the required degrees by ‘the usual 
process (and even on the neo-Ludwig view it is the glandular 
tubules which effect this concentration—not the capsules or 
an All that such an ordinary gland would require 
ould be an abundant ae supply. ie. it would have to be 
a near the aorta, and some device for protecting it a 
excessive pressure and 6 of flow. But the Vertebrate kidney 
exac oe answers to these requirements in both particulars. 
again contends that ‘‘ the Bowman-Heidenhain 
qeaey, faind therefore the Tubule cum Rete theory]... amounts 
to little more than the statement that the kidney secretes the 
urine by the vital activity of its cells’’ —and is therefore “a 
nebulous statement of the renal function,’ but the same may 
be said of any existing theory of secretion applied to the 9 eng : 
pancreatic or other gland. Further, if this statement ‘ 
defensive position... ig impregnable ”’ in virtue of its ‘ re 
losity,” the same may equally be said of a large part of Cushny’s 
defence of the neo-Ludwig theory. For example on page 41 it 
is stated as a “ grave objection’’ to the Bowman theory that 

! See the a account by Benjamin Moore (24) “ what may be 
alled the ‘‘ electr ’ theory of secretion and absorption—a theor 
whieh largely obviates the assumed ission peters of 
water to and from the lymph for the conveyance of sufficient quant 
of subst eted or ab . £e ot aw hat } 
quantities of water are assumed to be absorbed and elimina in th 
absorption of oxygen and fresh-water by the external gills 
n from 
of Fishes and Urodeles, nor from the blood by the oxygen gland of the 
bladder ot th many teleost fishes, and I do not understand why it should be 
assumed that the kidney sho — need to adopt what Starling ——. sc 
such ‘‘a clumsy way Of arriving at a urine, whose comositio 
adapted to the needs of the casteaal (40 p. 1288). When it is sala on 
gland cells can do in extracting substances from the blood, in concentra- 
ing them and in manufacturing new substances all precisely adapted to 
the requirements of the body as a whole, the crt that in the case of the 

kidn 1 hould have to exude the fluid part of its su in- 
toas continuous with the outside world a t a special gl d 
hould have to be developed to cate uch of this exuded 
h fluid as 
is of value to the st the 7 co rato of escape of the fluid allows, cid 
grotesque to say the | 
