502 MEMOIES OF THE NATIONAL ACADEMY OF SCIENCES. 



Plate XX. 



Metamorphosis of Alphcus heierocheUs from Beaufort, North Carolina, drawn from nature by W. K. 



Brooks. 



Fig. 1. Embryo just before hatching. 



Fig. 2. View of a larva which was captured in the tow net at Old Topsail Inlet, North Carolina, 

 June 25, 1883. It is about eighteen one-hundredths of an inch long, and is a little 

 younger than the one shown in PI. xvii. Fig. 3, and a little older than that shown in 

 Fig. 3 of this plate. 



Fig. 3. Ventral view of a larva little younger than Fig. 2. 



Fig. 4. Telson and swimming appendages of the larva shown in Fig. 3. 



Fig. 5 First maxilla of the same larva. 



Fig. (i. Second maxilla of the same larva. 



Fig. 7. First maxilliped of the same larva. 



Fig. 8. Second maxilliiied of the same larva. 



Fig. 9. Third maxilliped of the same larva. 



