AUTHOR’S ABSTRACT OF THIS PAPER ISSUED 
BY THE BIBLIOGRAPHIC SERVICE, MARCH 14 
THE FATE OF THE NEURAL CREST IN THE HEAD 
| OF THE URODELES 
F. L. LANDACRE 
Department of Anatomy, Ohio State University 
ELEVEN FIGURES 
CONTENTS 
MAG rOCUCELOMI eee Noh tere Lt ET IST ESSE EM cae Wee e ela clotengs eroteleraetes 1 
EISTORICATES KU CHirges ce ter esennes ote eae aes oes co Neuaraiolckal snares Sheie eueitionyaiecwrae was 3 
INS SRCTON DY Geese, oes Sis ARS oe Leteoee Ia eRe t  rre Pa 9 
hevoriainromshesneuralaeresbers. ces ts otek. ne Fate 6 nae ate cee oe sae eeiele cies 11 
The migration of the neural crest and its relation to the mesoderm....... 18 
ahevderiwvativessomune) lateral egtouderm.. 1. ss ciaaeactec.esslscraciowe acl 4 ae oe 22 
aM RO NA IME CUO ERIN eR Trina Wee vasa cues chav iopanel Bayshore tots. ofr evo) w et(arcemat onaTe ny hone evens se Beans 25 
The differentiation of the mesoderm and neural crest in the head.......... 28 
SUTIN yews API syn ew Pee CEN ahs: SEIU A 14h RAN YSN 2 Lights Mnaccihe ecg 32 
ILS Aer CNL |v ee hes OA Mee Ot I ORE pee we he > an Rae Se rae ase oe 34 
‘INTRODUCTION 
During the course of an investigation of the origin of the 
cerebral ganglia of the urodeles it became necessary to determine 
accurately the ventral limits to which the neural crest migrates. 
In the attempt to do this the distribution of the neural crest 
was found to be so extensive and to involve so much tissue of a 
non-nervous character that it was decided for the time being to 
discontinue the study of the cerebral ganglia and follow the 
history of that portion of the crest which is not concerned in the 
formation of these ganglia. 
. The ventral limit of ganglia into the composition of which the 
neural crest enters, namely, V, VII, IX, and X, is at the level 
of the epibranchial placodes, approximately at the dorsal border 
of the corresponding gill slit. The neural crest in all vertebrate 
_types, apparently, migrates ventral to this level beyond its 
ganglion-forming region and further is distributed in the head 
of the embryo anterior to the level of the gasserian ganglion. 
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