âSi IV" COM-KlilvNŒ INTBIi.NATKlN Al.i: l>K CKNKTlnlK. 



W'IiaL is llie cause of Ihc slioflonintj:? 



Encli phalanx iliirin^^ childhoful sliows, nnriii.illx . n lliin \h>u\ plair al ils 

 hase. Tliis ulalc is ralleil liii' " iMiipiivsi'î ": il is atlai-JiiMl lo llic larycr iidilidii 



l'i;;. li. — lia.liotri-.niih of llr:iclijil;iclyl.iiis Ii.iikI ..i 



— tlie " shafl " ol' llie bone — liy an inlorvcMiin^- laver of ijristli\ whicli. l)oinu: 

 transparent to the X rays, shows in a radiograpli as a blank space (figs 8 and '.M- 



In adult life Ihis pièce ol" grislle Ijeromes ossifled, and, with the sliafi and 

 epiphysis, forms one bone. 



Fig. 9 shows the epiphysis al Ihe l)asr ol' Ihe first phalanx, and one al llie 

 base of the Ihird, but the second phalanx is secn lo be wilhoul any eiiipliysis 

 except in the case of the middle fingcr. 



This rihsencc of the eplphyais accounts l'or a good deal of tho shortening of 

 the lingersin thèse people, but not for the whole of il, for il is obvions thaï the 

 S/(r(/< of the bone is of less than normal lenglh. and the first and third phalanges 

 also slightly shorler than they shonld be. There are as a matler of facl Ihree 

 factors concerned in the production of Ihc shortening of the middle phalanx. 



h' Shortness ot the shafl of the bone. 



'i"'^ Absence of the epiphysis. 



Thèse hâve alreadv been dealt with. 



