PLATE 19. 
1. 95. 4. Endoceras gemelliparum. (Pag. 60.) 
1 a. External view of the fragment. 
1 b. Transverse section of the smaller extremity, showing the siphuncle tube which joins the external margin ; 
within which are shown sections of the two embryo tubes. 
1 r. Longitudinal section of the specimen, d and e being the two enclosed tubes, one of them partially covered 
with stony matter. 
