122 



BULLETIN 82, U^riTED STATES NATIONAL MUSEUM. 



As the number of arms increases, adolescent antotomy, by acceleration oi 

 development, becomes a more and more fixed and fundamental character and 



Fig. 195. — Lateral view of type specimen of Oxymet 



takes place at progressively younfjer stages. Thus whereas in the case of species 

 with less than l.") arms the adult size is reached before the loss of any of the 



