The Bass and their Relatives 559 
this genus and in Calamus the second interhzmal spine is very 
greatly enlarged, its concave end formed like a quill-pen and 
Fie. 450.—Calamus bajonado (Bloch & Schneider), Jolt-head Porgy. Pez de Pluma. 
Family Sparide. 
including the posterior end of the large air-bladder. This 
arrangement presumably assists in hearing. Of the penfishes, 
Fie. 451.—Little-head Porgy, Calamus proridens Jordan & Gilbert. Key West. 
or pez de pluma, numerous species abound in tropical America, 
where they are valued as food. Of these the bajonado or 
jolt-head porgy (Calamus bajonado) is largest, most common 
