yg ART. 14— K. TENDO: 



distinguishable from the other. The tertiary lamella is characteristic 

 of the genicular portion proper. 



The lamellar arrangement of the cellwall in Amp. dilatata and its 

 allied species comes under a somewhat different category. The 

 tertiary lamella is only visible in the lower two thirds of the cells of 

 the genicular portion ; in other words the parts below the row of the 

 pits (ßgg. 11-12). It is hard in these species to recognize the layer 

 which corresponds to the secondary lamella of the other members. On 

 the other hand, a characteristic lamella is found at the meeting point 

 of the cells, which are always eight in number. The lamella develops 

 at the corner of the cell toward the center of the intercellular space to 

 fill it up. This lamella has some space between it and the mother 

 cellwall where some substance easily stained with hematoxylin is al- 

 ways found (fig. 12). 



The majority of the Corallinœ have connecting plates at the distal 

 ends of the cells both at the medulla and at the cortex. These plates 

 show the characteristic reaction of the pectin compound, while the 

 cellulose reaction is hard to detect. The connecting plates at the 

 articular ends of the extragenicnlar cells are especially rich in the 

 pectin compound. 



Those species which have conspicuous canals or rather perfora- 

 tions between the cells have their plates in the form of thin septa. 

 But when the canals are narrow passages, the colouring materials till 

 up the passages and prevent us from determining precise form of the 

 septa. 



In many species we often find large openings to allow the com- 

 munication between the cells, cf. Cor. vera' Japon. PI. II. figg. 21 

 and 23. These large openings seem to lack any kind of connecting 

 plates. Schmitz observed the protoplasma of the neighbouring cells 



1). Untersuch, ueber d. Zellkern cl. Thall. p. 122. 



