274 BULLETIN OF THE MUSEUM OF COMPARATIVE ZOOLOGY. 



EXPLANATION OF THE PLATES. 



[Note. — A detailed description of the specimens figured in the plates will be found on pp. 257-264. 

 Unless otherwise stated, the specimens are in the Museum of Comparative Zoology, and were obtained 

 from K. D. Atwood, Portland, Me. Those figured on Plate I. are reduced one half. Those figured on 

 Plate II. are of the natural size.] 



PLATE I. 



^ig. 1. 



Homarus Americanus, right chela. 



" 2. 





left 



" 



" 3. 





" right 



" 



" 4. 





right 



" 



" 5. 





left 



" 



" 6. 





right 



" 



" 7. 





left 



" 



" 8. 





right 



(< 



" 9. 





right 



" 



" 10. 





right 



" 



" 11. 





left 



tc 



" 12. 





right 



" 



" 13. 





right 



" 



" 14. 





right 



" 



" 15. 





left 



" 



" 16. 





left 



" 





(From 



Mus. Peabody 



Acad. Science, Salem, Mass.) 



17. Homarus Americanus, left chela, 



PLATE II. 



g- 1 



' 2 



! 3 



' 4 



' 5 



Homarus Americanus, dactylus of right chela. 



" " one of the small chelipeds. 



" " left chela. 



" " dactylus of right chela. 



Callinectes hastatus, left chela. 



(From Chesapeake Bay; coll. Dr. S. F. Clarke.) 



Homarus Americanus, right cheliped. 



" " left chela. 



Callinectes hastatus, left lateral part of the carapace with branched spine. 

 (Coll. M. C. Z.) 



Homarus Americanus, right chela. 



