

N. ROSÉN, STUDIES ON THE PLECTOGNATHS. 



13 



each tubercle, and that 

 top of the tubercle, if 

 epidermis is pierced or 



the epidermis is very thin över the 

 not actually pierced. Whether the 

 not, is a question of a Httle or no 



Ca -u 

 w O O 



s-i ,fl ** 

 bo . o 



c3 oc c3 



^ O) I 

 n fH J) 



*•"• -1h »3 



i o © 



O 00 © *S 



ÖS © -+J 



*S^ * o 

 * I O.^ 



^ ™ i— < 

 js © +-> © 



•2 .g a 



O 



© 

 C 

 fl 

 O 



o 

 o 



fr T3 c3 



importance. The fibrillated portion of the plate has a rather 

 complicated structure caused by the different direction of 

 the bundles of fibres. Six »triangles» can be distinguished, 

 the structure of which is as follows. One side of the triangle 

 forms one of the sides of the hexagonal plate. The apex of 



