432 DISEASE IN WILD MAMMALS AND BIRDS 
deformans is confined as a rule to the diaphyses. This 
ease was probably more closely allied to osteitis fibrosa 
cystica. Goldman (9) described examples in fowls and 
Rossweg (10) refers to specimens in domestic goats and 
monkeys. Many of these cases first come under obser- 
vation through fractures, an accident common to osteo- 
malacia, but very rare in well developed osteitis 
deformans. The diet of our monkeys was exceeding low 
in those substances essential to bone development. 
Sherman (11) has showTi that the calcium balance is reg- 
ulated to a certain extent by the calcium ingested, and 
that when the diet is poor in this element, the output 
materially exceeds the intake, a condition which is 
definitely changed when the animal is put on a diet high 
in calcium. 
So far as we could find there are no recorded studies 
of the mineral metabolism of beginning cases of Paget 's 
disease. It seems possible from the study of osteomalacia 
that the low mineral and otherwise faulty diet, added to 
the symptoms produced by that diet might so disturb the 
chemical equilibrium, directly through the neurotrophic 
mechanism or through the perversion of the ductless 
glands, that the mere addition of the lime water might 
entirely change the pathological picture. This is in 
accord mth the histology where the initial lesion is 
resorption of bone followed by irregular proliferation. 
It is also in accord with the probable chemistry of cal- 
cification. These animals all showed a lowered carbon- 
dioxide-carrying-power of the blood, and therefore 
lowered ability to carry calcium in solution. It is possible 
that Paget 's disease is but a stage in a deficiency disease, 
a faulty reparative response through a disordered neuro- 
trophic mechanism, or through a perversion of the glands 
governing calcium metabolism. Such perversion could 
(9) Verein Freiburger Aerzte, May 30, 1902. 
(10) Yet. Med. Inaug. Diss. Giessen, 1913. 
(11) Chemistry of Food and Nutrition, Macmillan, 1918. 
