BONE TISSUE. 



67 



still presents the old soft appearance. The cartilage cells lie 

 here, in an epiphysis, irregularly. In a diaphysis they would 

 be seen pressed together in longitudinal rows, or " ranked," 

 as it has been expressed. Below, however, we meet with a 

 cavernous tissue, the spaces of which, as a result of the prepa- 

 ration, in places no longer lodge the cartilage marrow con- 

 tents (a), while it still remains preserved in others (&, d). 

 Cloudy, dark trabeculae of the most irregular form constitute 

 the last remains of the liquefying decalcified cartilage (c). 

 Even these trabecular remains are deprived of further re- 

 pose. 



Fig. 64. — Transverse section from the femur of a human embryo of about eleven weeks ; a, a 

 transverse, and l>, a longitudinally divided medullary canal ; c, osteoblasts ; d, the more trans- 

 parent, younger, e, the older bone substance ; f, lacunae with the cells ; g, cells still limited 

 to the Osteoblast. 



If the contents of these cavernous passages are attentively 

 examined at this period, their peripheral cells are found to 

 have assumed an anomalous shape. They resemble, with 

 their cubical bodies (Fig. 64, c), an irregular, badly developed 

 cylinder epithelium. Gegenbaur, their discoverer, has 



