PROF. T. WING ATE TODD ON OSTEOMALACIA. • 859 



Summary. 



1. Osteomalacia, or so-called spontaneous generalised bone- 

 softening, is not a simple decalcification of bone, but a re- 

 organisation of bone as an organ, in which the loss of osseous 

 tissue is not brought about by osteoclasts. 



2. From this it is evident that the cell-masses known by the 

 name of " osteoclasts " are not indispensable in the transformation 

 of bone to less specialised tissue. 



3. The disease may be infectious in oi-igin. If so, the evidence 

 at our disposal points to the nervous system as the site of infec- 

 tion. The bone-changes appear to be the symptoms consequent 

 on the nervous lesion. 



References. 



(1) Gayet et Bonnet.— " Contribution a Fetude des osteo- 



malacies." Revue de Chir. vol. xxiii. pp. 44, 228, 1901. 



(2) MoRPURGO. — " Ueber eine infectiose Form der Knochen- 



briichigkeit bei weissen Ratten." Verhandl. d. Deutschen 

 Path. Ges. vol. iii. p. 40, 1901. 



(3) MoRPURGO. — " Durch Infection hervorgerufene malacische 



und rachitische Skeletveriinderungen an jungen weissen 

 Ratten." Cent. f. Allg. Path. u. Path. Anat. Bd. xiii. 

 p. 113, 1902. 



(4) Ziegler. — " Ueber Osteotabes infantum u. Rachitis." Cent. 



f. Allg. Path. u. Path. Anat. Bd. xiii. p. 865, 1902. 



(5) Retterer. — " Structure et histog^nese de I'os." Journ. de 



I'Anat. et de la Physiol, p. 561 et seq., 1905. 



(6) MoRPURGO. — " Ueber die infectiose Osteomalacie und 



Rachitis der weissen Ratten." Verhandl. d. Deutschen 

 Path. Ges. vol. xi. p. 282, 1907. 



(7) Basset. — " Anatomie pathologique de I'Osteomalacie spon- 



tanee et experimentale." Arch, de Med. Experimentale, 

 T.'xviii. p. 713, 1906. 



(8) Schonenberger. — " Ueber Osteomalacie mit multiplen 



Riesensarkomen und multiplen Fracturen." Yirchow's 

 Archiv, Bd. clxv. p. 189, 1901. 



(9) Todd. — " The Arterial Lesion in Cases of Cervical Rib." 



Journ. Anat. & PhysioL vol. xlvii., 1913. 

 (10) Fox. — The 40th Annual Report of the Board of Directors 

 of the Zoological Society of Philadelphia, p. 55, 1912. 



EXPLANATION OF THE PLATES. 



Plate LXXXVII. 



Pig. 1. Right Radius from 3-ouug Anubis Baboon {Gynoceplialus anubis). Advanced 

 stage of osteomalacia. 

 Note large size and dark colour of marrow cavity. The dart appearance is 

 due to the large quantitj^ of red marrow. The rarefaction of bone and the 

 progression of the osteoporosis from marrow-cavity outwards is well shown 

 in this photograph. The compact tissue can be seen to have been replaced 

 by spongy bone. 



Proc. Zool. Soc— 1913, No. LVII. 57 



