CONNECTIVE TISSUE. 223 



this extremely delicate reticulum I could not obtain, as all trials 

 with silver and gold staining of bone proved to be failures. 



The bone-corpuscles, as well as all other connective-tissue 

 corpuscles, are formations of living matter, which in a juvenile 

 condition are found to be compact, homogeneous, or vacuoled 

 lumps, while in full development they are nucleated plastids. 

 Their shape varies, to some extent, with that of the territories of 

 basis-substance in which they exist. We find globular bone- 

 corpuscles, which have assumed a star-shape by the appearance 

 of numerous radiating offshoots, in the earliest formations of 

 globular territories. We also meet with globular bone-corpuscles 

 at the peripheral portions of fully developed Haversian systems, 

 owing to the presence of the first formed territories of this sys- 

 tem, and again in the interstitial bone-tissue between the systems, 

 in places where no lamellae are formed. In striated or lamellated 

 bone-tissue the corpuscles are oblong or spindle-shaped bodies, 

 slightly bent in the direction of the striae or lamellae, intercon- 

 nected by larger offshoots, emanating from both poles, and by 

 numerous delicate offshoots, traversing the basis-substance in a 

 rectangular direction. The latter offshoots arise at right angles 

 from both the periphery of the corpuscles and their larger longi- 

 tudinal branches. In the Haversian systems the bone- corpuscles 

 are slightly flattened, and in longitudinal sections exhibit their 

 broadest oblong surface whenever the razor strikes a peripheral 

 portion of a Haversian system, while they have the appearance of 

 narrow spindles, when the razor runs through the middle of a 

 lamellated system. In transverse sections of the system the 

 corpuscles exhibit irregular shapes, and again vary in their diam- 

 eters according to the depth to which they are cut by the razor. 

 A spindle will necessarily look broader if the section has been 

 made transversely through the middle, and narrow if near the 

 ends. 



Varieties of Bone-tissue. There are two kinds of bone-tissue, 

 which, in the fully developed subject, however, are always com- 

 bined with each other, viz. : the cancellous, epiphyseal, or spongy 

 bone-tissue, and the compact or cortical bone-tissue. 



(a) Cancellous, Epiphyseal, or Spongy Bone-tissue is built 

 up by trabeculae, arranged as a frame-work inclosing the medul- 

 lary spaces. It is the only kind found in early stages of develop- 

 ment of bone. In the fourth, fifth, and sixth months of 

 embryonal life of human beings, and in dogs, cats, and rabbits 

 at birth, no other bone-tissue but the cancellous is found. In 



