JOURNAL 



OF 



MORPHOLOGY 



ForxDED BY C. O. Whitman 



EDITED BY 



J. S. KIXGSLEY 



University of Illinois 

 Urbana, 111. 



with the collaboration of 

 Gary N. Calkins Edwin G. Conklin C. E. .McClung 



Columbia University Priiceton University University of Pennsylvania 



W. M. Wheeler William Patten 



Biissey Institution, Harvard University D.irtmouth College 



volu:me 30 



1917-18 



THE WISTAR INSTITUTE OF ANATOMY AND BIOLOGY 



PHILADELPHIA 



