Fig. 314 — (Continued) Types and development of bone. (E) Diagram showing inva- 

 sion of cartilage by perichondria! vascular buds, preparatory to deposition of bony sub- 

 stance on cartilaginous spicules produced by erosion of cartilage (compare with fig. 313, 

 D). (F) The formation of spongy bone within, by deposition of bony substance on 

 cartilaginous spicules. See spicule "A." Compact bone is deposited on outer surface of 

 cartilaginous replica of future bone by periosteal osteoblasts, forming bony cylinder of 

 compact bone. (Redrawn and modified from Bremer, 1936, Textbook of Histology, Phila- 

 delphia, Blakiston.) (G) Formation of membrane bone from jaw of pig embryo. (Re- 

 drawn and modified from Bremer, 1936, Textbook of Histology, Philadelphia, Blakiston.) 

 (H) Bone destruction and resorption. Observe osseous globules within substance of osteo- 

 clast. (From Jordan, '21, Anat. Rec, 20.) 



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