U. S. B. F— Doc. 



Plate XI, 



FIG. 1.— OKLu:. rH ._.b. EARDRiJt.l NORMAL IN FEMALE, EN- 

 LARGED IN MALE. 

 (After Wright, Carnegie Publ. No. 197.) 



FIG. 2.— LEOPARD FROGS. PECTORAL EMBRACE. 

 (After Wright, Carnegie Publ. No. 197.) 



f IG. j.— TREE TOADi. AXILLAKr EMBRACE. 

 (After Wright, Carnegie Publ. No. 197.) 



FIG. 4.— COUCH'S SPADEFOOTS. 

 INGUINAL EMBRACE. 



