PLATE II. 



HlSTIOSTOMA EOSTEO-SEEEATUM, page 208. 



Length, $ about *55 mm., $ about *4 mm. 



Fig. 1. Adult 2 , dorsal view, X 85. 



2. Adult ? , ventral view, X 85. 



3. Adult $ , dorsal view, X 85. 



4. Adult $ , ventral view, X 85. 



5. Hypopial nymph, dorsal view, X 200. 



6. Hypopial nymph, ventral view, X 200. 



7. Hypopial nymph, mouth-opening, lip, and 



sternum from below, X 500. 



8. Hypopial nymph, sucker-plate and anus, x 



500. 



9. Hypopial nymph, first leg from below, X 500. 

 10. Hypopial nymph, fourth leg turned forward at 



the genual, as the third and fourth legs 

 generally are when the creature is not 

 moving. 



