AnatoMij oj the Kingfishers. 117 



for the degeneration of the superficial muscle. The increase 

 is notable in some of the eutaxic forms, e. g. Ceryle 

 americana and C. inda. 



Gastrocnemius. — In Dacelo (fig. 15, tib., mid., ext.) this 

 muscle has the usual three heads, the middle head being the 

 smallest and connected with the internal adductor. It is 

 similar in the other Kingfishers, except that in Halcyon rvfa 

 all three divisions are reduced to tendon, perhaps an 

 individual abnormality. I figure the muscle, as its arrange- 

 ment in different Avian groups has considerable interest. 



Fisr. 15. 



..adoL. 



Leo:-mnscles of Dacelo gigantea. 



fern., fetnur ; add., adductor ; semi-m., semi-membranosiis ; e.rt., mid., 



tib., external, middle, and tibial heads of the gastrocnemius. 



Plantaris. — This is small and normal in all. 



Flexores perf or antes et perforati of the second and third 

 digits are similar in all, except that in Ceyx the muscle of 

 the index is absent. 



Flexores perforati of digits ii., iii., iv. — In Dacelo (fig. 16, 

 p. 118) this muscle-complex arises by two heads, vchidi join 

 and give rise to the tendons for the digits. One head is fleshy 

 and from between the condyles of the femur; the otlier also 

 is fleshy and arises, rather unusually, from the fibula and 



