4b4 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



Plate XL 



Fig. 25. Embryo nearly ready to hatch, released from the egg membranes. x70. Some food 



yolk is still unabsorbed; swimming hairs very rudimentary; compare Fig. 11. 

 Fig. 26. Eight first antenna of older larva, x 70. 

 Fig. 27. Profile view of hinder end of abdomen of same larva. x28. 

 Fig. 28. Second maxilla of same larva, x 276. 

 Fig. 29. Mandible of same larva, x 276. 

 Fig. 30. First maxilla of same larva. x276. 

 Fig. 31. Portion of third maxilliped of same larva, x 70. 

 Fig. 32. Terminal segment of second pereiopod of same larva, x 70. 

 Fig. 33. First pereiopod of same larva. x70. 

 Fig. 34. Portions of third, iourth, and rudimentary fifth pereiopods of same larva, x 70. 



REFERENCE LETTERS. 



A. I, first auteiina. 



A. II, second .antenna. 



Md., mandible. 



ilxpd. I, III, lirst anil third maxillipeds. 



R., rostrum. 



Til,., Th. 1, first maxilliped. 



Th. 3-Th. 5, third to fifth maxiUipeds. 



1, first maxilliped. 



