168 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 8 



PLATE 17 



Thyonacta mexicana, new species p. 101 



1-5. Baskets from external layer of integument. 



6-9. Smaller knobbed buttons from inner layer of integu- 

 ment. 



10. Large knobbed button from inner layer of integu- 

 ment. 



11-13. Supporting plates, knobbed and smooth, from tube 

 feet. 



