STRUCTURE OF BONE. 19 



lamellae ; indeed, the medullary canal of long bones may be con- 

 sidered as a single Haversian canal exceedingly dilated. The oval 

 corpuscules* are minute cells, from which are given off a number of 

 radiating and branching tubuli,f which anastomose with the cor- 

 responding tubuli of neighbouring cells. The cells and tubuli are 

 filled with calcareous substance : hence they have been named 

 calcigerous cells and tubuli. 



Deutsch, in his excellent researchesj on the minute structure of 

 bone, has described certain radiating lines which traverse the thick- 

 ness of the concentric lamellae. They are thus referred to by 

 Muller. " It is very remarkable that the thickness of the lamellae 

 is traversed by numerous lines which are separated by very small 

 intervals, arid which correspond in length to the thickness of the 

 lamellae, namely, 7 ^ 7 th of a line. Deutsch supposes these lines to 

 be tubes in which the calcareous matter of the bones is deposited(?) ; 

 if one lamella be separated from another the ends of the lines are 

 seen, he says, of a triangular form. The existence of these fine 

 tubes(?) was hitherto quite unknown ; but it is not probable that 

 they serve for the reception of the calcareous matter, for the first 

 appearance of ossification is in the form of a microscopic net- 

 work !"|| Having been engaged during the past summer (1841), 

 and being still occupied with the investigation of the minute struc- 

 sture of bone, I have had the good fortune to discover the true 

 nature of the lines thus alluded to by Deutsch and Muller. I have 

 found that the corpuscules of Purkinje are arranged very differently 

 in different kinds of bones ; that in flat bones, and in the thin lamella 

 of cellular bones, they exist in great numbers, are of considerable 

 size, and are disposed with no regularity. Their tubuli are short, 

 tapering, and tortuous, and proceed irregularly from every part of 

 the surface of the corpuscules. In the long bones, the corpuscules are 

 apparently smaller than the preceding, they are oval and flattened, 

 and lie between the concentric lamellae. Their tubuli are long and 

 only slightly undulating, and diminish very gradually towards their 

 termination, where they communicate with the tubuli of other cor- 



* Discovered by Purkinje. They are about ^th of a line through their long- 

 diameter. 



t Discovered by Muller. They are very distinct. Their larger trunks are about 

 . i __th of a line in diameter. 



I De penitiori ossium structure observationes. Dissert, inaug. Vratisl. 



Physiology, Translation, p. 378. 



|| In reference to this question, Dr. Bayly, the translator of Muller, observes, 

 " Miescher does not confirm Deutsch's statement as to the still more minute tubes 

 traversing the concentric lamellse, although he perceived the radiated appearance 

 around the larger canals, which was produced by dots or short lines, which do not 

 occupy the whole thickness of each lamella. Some of the lines appear to traverse 

 more than one lamella, though the majority, as Miescher describes, are very short. 

 They appear more like the separations between the granules of cartilage that form the 

 lamellae than distinct tubes." Dr. Bayly has given the figure of a transverse 

 section of an Haversian canal, in which Deutsch and Miescher's views are clearly 

 illustrated. 



