124 Frogs, and their Contributions to Science. 



as all the vertebrae together, and reaching to the symphysis 

 or union of the iliac bones, liibs are wholly wanting, a 

 fact which bears upon his method of respiration. Like 

 man the frog rejoices in his upper and his lower extremities, 

 particularly his lower. He has his femur, and his humer- 

 us, his radius and ulna united in a single bone, his tibia, 

 and fibula also united, his carpal and metacarpal, tarsal, 

 and metatarsal bones, and phalanges for his fingers and 

 his toes. 



The muscular tissue that invests the skeleton we de- 

 scribe, is of whitish appearance, very firm in texture and 

 very susceptible to galvanic action. Of its delicacy as a 

 thing of diet, or its beauty as a thing to be studied under 

 the microscope, we will not now speak. It is with little 

 difficulty one can pick from the thigh of the frog muscles 

 that are analogous to those of the thigh of man. The 

 flexors and extensors, the recti, the glutei, the gastro- 

 cnemii are all to be found well developed, and suggest 

 from their form, origin and insertion, a series of movements 

 similar to those made by man. Thus in swimming, man 

 and the frog strike out peculiarly alike. It may be noticed 

 here in regard to his aquatic feats, that he has not the 

 power of balancing himself and moving about at different 

 depths of the water like a fish, but is either at the surface 

 or closely hugging the bottom, and the same is true of him 

 to a certain degree even in the tadpole state. 



A tough membranous skin invests the body, webbing 

 the toes of the hind feet only, green and marked with 

 dark pigment patches on the back, and tawny or golden, 

 colored about the throat, and full of pores that serve alike 

 as important aids in respiration and for the secretion of 

 the slimy mucus that keeps the body cool, glistening, 

 supple, and difficult to hold when caught by any preying 

 enemy. The color of this tissue is not constant, but 

 darker, greener, brighter or more leaden-hued on some 



