THE CHONDROCRANIUM IN THE 

 ICHTHYOPSIDA.i 



BY GUY MONROE WINSLOW. 



CONTENTS. 



PAGE 



Introduction, 87 



Amblystoma, 90 



Desmoguathus, 99 



Plethodon, 100 



Necturus, 101 



Amphiuraa, 104 



The Chondrocraniiim in tlie Urodela, 108 



Pipa, 110 



Contrasts between Urodela and Anura, 112 



Ichtliyopliis, 115 



The Chondrocranium in the Csecilia, 120 



Polypterus, 122 



Trout. 124 



The Chondrocranium in the Fishes, 126 



Protopterus, 128 



The Chondrocranium in the Dipnoi, 131 



Literature, 134 



Explanation of Figures, 138 



» Studies from the Biological Laboratorj' of Tufts College, under the direction 

 of .1. S. Kingsley, No. xix. 



I wish here to give credit for some of the material used in these studies. 

 The Necturus larvce were given to me by Miss Julia B. Piatt; for Pipa I am 

 Indebted to the late Professor E. D. Cope; Professor Robert Wiedersheim fur- 

 nished me witli the Protopterus material and I began the study of the chon- 

 drocranium of this Dipnoan in his laboratory. For Amphiuma I am indebted 

 to Professor O. P. Hay, the first to find embryos of this interesting Urodele, 

 and to the late Professor .lohn A. Ryder, who kindly turned over to me the 

 embryos sent him by Doctor Souchon of New Orleans. The embryo Cxcilians 

 were given me by the cousins Paul and Fritz Sarasin and were a part of the 

 material which formed the basis of their splendid monograph. To all these I 

 return my best thanks. 



J.S. KiNOSLKY. 



(87) 



