l6 THE SESAMOID ARTICULAR 



Pterengraulis atherinoides. 



Though much larger and of more dense bone, the sesamoid articular 

 is essentially as in Coilia nasus. 



Engraulis encrasicholus. 



In this species the sesamoid articular is large and essentially as in 

 Pterengraulis and Coilia, being as large as in the former. Dr. Ridewood 

 reports it missing, it having doubtless been lost in preparing the speci- 

 men, for it is easily pulled away and remains attached to its tendon. 



Pterothrissus gissu (Bathythrissa dorsalis). 



Dr. Ridewood reports the sesamoid articular unossified in this form. 

 It is, however, very well developed, and is placed saddle-like over Meckel's 

 cartilage remote from the endosteal process. It, like Engraulis, has this 

 bone so loosely attached that it is liable to be removed with its tendon. 



THE SALMONOID FISHES. 

 Salmo irideus. 



A small sesamoid articular is loosely attached against the ectosteal 

 part of the articular remote from the endosteal part, and is partly covered 

 by the slender Meckel's cartilage. 



Osmerus dent ex. 

 In this the sesamoid articular is essentially as in Salmo. 



Thymallus signifer. 



The sesamoid articular is moderately large, and on the upper edge 

 of Meckel's cartilage remote from the endosteal part of the articular. 



Argyrosomus hoyi. 



In this form the sesamoid articular is rather large, situated on the 

 upper surface of Meckel's cartilage, and in contact with both the endo- 

 steal and ectosteal parts of the articular. 



THE SYNODONTID^E. 



Synodus lucioceps. 



In this the sesamoid articular is large. It is attached to the endo- 

 steal part of the articular at the inner side and posterior end, and arches 

 over Meckel's cartilage to the ectosteal part of the articular. 



