I 



174 T. C. WHITE ON SECTIONS OF HARD TISSUES. 



cavity will be found filled with a secondary dentine, presenting some 

 resemblance to the regular dentine, but with the tubes more sparsely 

 distributed, and curving irregularly through the mass. 



In fangs of teeth that have been painful for some time, attended 

 by much inflammatory action, fresh bone is added to the cementum, 

 and what is termed an " exostosis " is produced; such a one as this I 

 have placed under the microscope, where the layers may be observed 

 succeeding each other in the order of the inflammatory exacerbations. 



In some teeth presenting a rough, ridgy, and honey-combed 

 appearance, the dentinal tubuli are found traversing large globules 

 of the dentine, as if originally the dentine had been put together in 

 large globules which had never become fused, but had left inter- 

 spaces between each globule. This form of dentine is generally found 

 in teeth of delicate children where some illness has interfered with 

 the process of deposition, and hence the imperfect calcification. 

 These teeth are best mounted by laying the section on a tolerably 

 stiff layer of balsam, and when thoroughly embedded in it, cover it 

 with balsam almost as stiff as that placed under it, that no absorp- 

 tion may take place which would render the interspaces too trans- 

 parent and invisible. 



On Papers for the Club. 

 (Read August 26th, 1870.) 



In looking over the past records of the Quekett Microscopical 

 Club nothing has so often forced itself upon my attention as the 

 note " Papers Wanted," and no greater difficulty presents itself 

 now than that want of papers " on topics of interest, that discussion 

 of doubtful points," which will be found enumerated as among the 

 objects for which the Club was founded. From whence, then, 

 arises this want ? How shall this difficulty be surmounted ? 



First, I would ask, why do members hold back their communi- 

 cations ? For all must have some they could make. What do they 

 consider is required of them ? And here let me say I believe we strike 

 at the fountain head of all that reticence so marked of late at our 

 meetings. I believe the feeling, if not openly expressed, is at least 

 tacitly felt, that the Quekett Microscopical Club is a scientific 

 society, and accordingly that communications made to it must 



