author's abstract of this paper '.SSUED 



BY the bibliographic SERVICE, MARCH 2 



PHARYNGEAL DERIVATIVES OF AMBLYSTOMA^ 



FRANCIS MARSH BALDWIN 



FORTY-SEVEN FIGURES (tWO PLATES) 



CONTENTS 



I. Introduction 606 



Material and methods 607 



II. Observations 608 



1 . Thymus bodies 608 



A. Larvae 8 mm. long 608 



B. Larvae 9.5 mm. long 611 



C. Larvae 10-12 mm. long 613 



D. Larvae 13-15 mm. long 6l6 



E. Larvae 19-20 mm. long 617 



F. Larvae 35-45 mm. long 619 



G. Transforming larvae 620 



H. Thymus gland of adult 622 



2. Thyreoid gland 624 



A. Larvae 5 mm. long 624 



B. Larvae 8 mm. long 625 



C. Larvae 9.5-11 mm. long 627 



D. Larvae 13 mm. long 630 



E. Larvae 15 mm. long 631 



F. Larvae 19 mm. long 633 



G. Larvae 26 mm. long 634 



H. Larvae 35 mm. long 634 



I. Larvae 39 mm. long 635 



J. Larvae 45 mm. long 635 



K. Larvae transforming 635 



L. Thyreoid gland of adult 637 



1 Contributions from the Zoological Laboratories of the University of Illinois 

 No. 103. 



605 



JOURNAL OF MORPHOLOQT, VOL. 30, NO. 2 



