Reed and Lloyd. — Spines of Catfishes 205 



From observations such as those mentioned above it 

 appears that the spines of the common catfishes repre- 

 sent modifications of soft rays through ankylosis of the 

 segments and dichotomous divisions rather than suppres- 

 sion of those parts as in the spiny-rayed forms. In 

 other words, the catfish spine is a modification of a 

 definitive soft ray rather than that of its embryonic 

 rudiments. The presence of spines in catfishes becomes 

 harmonious, therefore, with their rank among the soft- 

 rayed groups. 



