In this work, we have quoted from some forty-five or fifty workers, 

 and most of these excerpts appear under this caption of Notes. These 

 will show some of the contributors to the study of this group. These 

 workers have very generously granted us permission to quote from 

 their pertinent published works. To the numerous specialists, scient- 

 ists, friends and old students who helped us to acquire or to examine 

 specimens for a monograph, we also acknowledge indebtedness in this 

 volume. Finally, to the publishers we extend our gratitude for helpful 

 suggestions made both before and during the printing of this volume. 



Key to Families 



Fig. i. American bell toad. Ascaphus truei. I. Short anal tube of 

 female. 2. Light band across head. 3. Rear of femur. 4. Tail of male, 

 extending from ventral side of body. 5. Vent. 6. Horny excrescences, 

 (secondary breeding characters) of the male. 



a. Male with tail-like process; female with short anal tube; 

 no tympanum; pupil elliptically vertical; upper jaw 

 toothed; short ribs present; light band across head; size 

 small, 1 1/8-2 inches (28-51 mm.). 



Ribbed toads. Discoglossidae. Plate V. 



aa. Male without tail; female without short anal tube; ribs 



absent. 



b. Waist wide; body broad and thick; hind limbs short. 



c. With transverse fold of skin across head behind 



eyes; size small, 3/4-1 5/8 inches (19-41 mm.); 



no tympanum; no parotoids; snout pointed; head 



narrow; fingers and toes without webs except 



slight in Hypopachus; eyes small and depressed. 



Narrow-mouthed toads. Brevicipitidae. 

 Plates LXXIX-LXXXI. 



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