494 MEMOIRS OF THE NATIONAL ACADEMY OF SCIENOES. 



Plate XVI. 



Metamorphosis of Alpheus, drawn by W. K. Brooks and F. H. Herrick. 



Fig. 1. Third larval stage of Alpheus minor from below, drawn by W. K. Brooks. 



Fig. 2. Second larval stage of Alpheus minor, about one- tenth of an inch long, drawn from below 



by W. K. Brooks. 

 Fig. 3. Telson of the Nassau form of Alpheus heterochelis during the second larval stage, drawn 



at 10 a. m., April 17, 1887, by F. H. Herrick. 

 Fig. 4. Second antenna of Alpheus minor during the first larval stage, from the inside drawn by 



W. K. Brooks, May 13, 1881, D. 2. (Zeiss lenses.) 

 Fig. 5. First and second maxillae of the Nassau form of Alpheus heterochelis during the fourth 



larval stage, drawn by W. K. Brooks from a sketch by F. H. Herrick. The larva at 



this stage is shown in PI. xii. Fig. 3. 

 Fig. 6. First maxilla o{ Alpheus minor (iin'ntg the first larval stage, drawn at Beaufort, June 2, 



1881, by W. K. Brooks, I). 2. 

 Fig. 7. Second maxilla of the same larva. 

 Fig. 8. Mandible of the same larva. 



