NO. 9 A NEW ORDER OF CRUSTACEA — PENNAK AND ZINN TT 



EXPLANATION OF PLATES 

 Plate i 

 Derocheilocaris typicus 



1. \'ential view of head region of adult showing relationships between labrum 



and basal portions of first antennae through maxillipeds. 



2. Dorsal view of cephalic shield, showing notches, sutures, and ocelli. 



3. Lateral view of adult. 



4. Lateral view of abdominal segment showing detailed structure of a chitinous 



trough. 



5. Lateral view of posterior part of head and postcephalosome showing details 



of chitinous troughs. 



6. Lateral view of posterior end. 



7. Ventral view of first thoracic segment showing region of genital opening. 

 (Large scale refers to figure 3; small scale refers to all other figures.) 



Plate 2 

 Derocheilocaris typiais 



1. First antenna of adult. 



2. Second antenna of adult. 



3. Mandible of adult. 



4. First maxilla of adult. 



5. Second maxilla of adult. 



6. Maxilliped of adult. 



7. Right thoracic appendages of adult. 



8. Second antenna of fifth larval stage. 



9. Mandible of fifth larval stage. 



