314 THE WONDER OF LIFE 



that tht- larvije cause tt pearls. It may be a case of two 

 parallel diseases, r<-><ti}'-vftU to the case of a dog infected 

 simultaneous] v ruis and mange. Mr. Jameson 



maintains tkat t*?ar*s :^~*r round nuclei of some variety 

 of shell-substttJ^ fxUfciVi when the normal rhythm of 

 secretion in i:-rh.aH"i 



A vorv f c%c formation of pearls has been 



road*- by A.. Ri--bf*i tu Uw? ase of a freshwater mussel 

 ; which is common, for instance, 



i*wwtak& Breams of Bavaria. His obser- 

 *: 7 \-rhat pearls aresepulchres 



. . He finds that they arise 



Distance, which 



Bln B iBM) feeauM irtwAtttf lo H 9 H8 .K'-.Oll 

 nigism 9 H* I 69 n ehsDq owl S nJwo^ s of 

 1 he external 



^Hu4ij 'f skin 



; ; . 



entre. 

 rise to 

 



begin -ittached to 



tiif ;rom shell-concre- 



tiomi whi' 'led bodies, and do not 



show any <<;. -ording to Rubbell, the 



innermost, or -f. the shell, is divided, 



at certain plac^ r and an outer stratum 



by a dear intermediate layer, which is also seen iiiaide 

 the pefftfei 



It pearls and p 



Keeping 



