THE SESAMOID ARTICULAR 29 



and one to its posterior end. Opposite the base of each tendon there 

 is a rather deep depression in the articular, which show on the outer 

 surface of the mandible as very thin spots where the bone is easily broken 

 through. I have found no other example where two tendons join the 

 sesamoid articular. The relationship of the tendons is herein described 

 in the section devoted to adductor muscles. 



Promethichthys prometheus, Lepidopus caudatus, Trichiurus lepturus. 



The sesamoid articular is similar to that in the fishes of the family 

 Scombridae, rather small, more or less between the ectosteal plate and 

 Meckel's cartilage, and just at the anterior end of the endosteal plate, 

 with which it is in contact except in Lepidopus. 



Pomatomus saltatrix, Palometa triacanthus, Peprilus paru. 



The sesamoid articular is on the upper surface of Meckel's cartilage 

 and the endosteal process, and on its outer surface it is against the ecto- 

 steal plate. In Rachycentron it is rather large and only slightly in con- 

 tact with the endosteal process. 



THE PERCOID FISHES. 



Lobotes pacificus, Pomoxys sparoides, Priacanthus catalufa, Apogon 

 maculatus, Sciaena stellifera, Nebris occidentalis, Mentacirrhus 

 alburus, Polycirrhus dumerili. 



In these the sesamoid articular is moderate in size or small, and is 

 situated against the ectosteal plate with the endosteal process and Meckel's 

 cartilage overlying it and hiding it from view more or less as it is viewed 

 from the side. 



Dentex vulgaris, Sargus rondeletii, Archosargus probatocephalus, 

 Pagrus vulgaris, Diplodus argyrops, Pagrellus erythrynus, 

 Lutianus aya, Girella nigricans, Oblata melanura. 



The sesamoid articular is very much as in Lobotes et. al., but is on 

 top of the endosteal process and Meckel's cartilage, and very little, if at 

 all, hidden behind them. In Archosargus and Pagrus it is much more 

 over the endosteal process than over Meckel's cartilage. In Diplodus 

 this condition is reversed. In the others it is about equally over both. 



