INTRODUCTION 5 



form called the surangular confusing it with the surangular of Ganoids 

 and that Ridewood says, is "merely the endosteal articular displaced." 



Erdl, in his work on Gymnarchus, labeled the sesamoid articular, in 

 both German and Latin, the kronenforsatz des Unterkiefers, pars coro- 

 noidea mandibulae. He thus, doubtless, as Cope did later, considered 

 it the homolog of the coronoid of reptiles. 



Bridge in 1877 described the bone in Amiatus that I have herein 

 homologized as the sesamoid articular. He termed it simply ossicle C, 

 but since that time every anatomist who has worked on Amiatus has 

 referred to it as "ossicle C of Bridge." 



The last author to write of this bone was Ridewood (Proc. Zool. 

 Soc. Lond., 1904, p. 72), whom I follow in the use of the term 'sesamoid 

 articular' as the best suggested for it. It is the Anglicized form of 

 Vetter's Sesamoidverknocherung. He gives a history of the literature 

 of the bone since the time of Cope, which I need not here repeat. Among 

 the papers touched upon he gives undeserved prominence to a hastily 

 prepared foot-note published by me in 1899 (Proc. U. S. Nat. Mus., 

 XXII), in which I listed various unrelated forms that possessed a sesa- 

 moid articular. My material was such prepared skeletons as happened to 

 be at hand, and the note was published purely with the object of showing 

 the worthlessness of the bone in taxonomy as used by Cope. As my 

 discussion was based on Cope's paper I followed him in the use of 

 the term 'coronoid bone' without thought of homology. 



Most of the examples I reported upon were adult; and because the 

 bone happened to be missing in a young individual of Mugil, the question 

 was brought up as to whether it was not the ossified end of the tendon, 

 that is always attached to it, developed with age. This seemed more 

 probable at that time, as I was investigating the skeleton of Dallia in 

 which the posttemporal ligament ossifies rather late in life. In the young 

 Mugil referred to the bone was doubtless lost in preparing the skeleton, 

 for I find it well developed in much smaller individuals that those re- 

 ported upon. 



It has seemed most convenient for the needs of this paper to follow 

 no scheme of grouping. The captions are not at all coordinate in value, 

 nor are they consistent in terminology. For instance, the small orders 

 of Ganoids together with the lung fishes are under one caption. "The 

 eels" includes two orders; "the clupeoid fishes" is of superfamily rank; 

 and the spiny-rayed fishes are grouped under such comprehensive cap- 

 tions as "the blennies" or "the mailed-cheeked fishes," or even under 

 family names. 



