,4 



<4 



Figure 61. — Electron micrograph of the ligament of C. mrgniica sectioned parallel to the fibrils. 



pelecypods whicli have no true nacre (0. edvli.'i, 

 0. tulipa, Yfildia, Acta, and others) were found to 

 consist "of heterogenous niateriul, tlie more repre- 

 sentative elements of which are amorphous, vitre- 

 ous phites, sometimes granuhxr and devoid of 

 visible (or unquestionable) pores." (1950, p. 



30)." In the absence of ultrasonic equipment in 

 my laboratory this method could not be used at 

 Woods Hole, Mass. Comparison of figures pub- 

 lished by Gregoire and his associates with the 

 photograpii reproduced in figure 62 suggests that 



5 Translation bv Paul S. GaUsofF. 



THE LIGAMENT 



55 



