remains of what to call the element that has not been lost. Ferraris (1988) did not 

 discuss this bone, but in his illustrations of various suspensoria he indicated that the 

 entopterygoid was omitted. This may be the currently accepted name for the bone 

 in question, at least in other teleosts (Cailliet et al. 1986), but there is little 

 uniformity in terminology. Nevertheless, I prefer to consider the above element a 

 mesopterygoid, equivalent to the same bone of Gosline (1975) and Fink and Fink 

 (1981). 



The mesopterygoid in ageneiosids is a moderately large bone, superficially 

 contacting the vomer anteromedially, passing medial to the palatine, and abutting 

 near or loosely suturing with the anterior margin of the metapterygoid. Its shape 

 varies from broadly triangular to quadrangular. In most species the mesopterygoid 

 does not extend very far posterodorsally, but in A. pardalis it is relatively long, and in 

 A. n. sp. it extends over the entire dorsal margin of the metapterygoid and contacts 

 the anterodorsal comer of the quadrate. *, . 



The shape and orientation of the combined elements of the suspensorium 

 vary somewhat among species, and appears to be correlated with the degree of 

 flattening of the head. In A. atronasus,A. brevis, and Tetranemadchthys, the 

 suspensoria are not extremely elongated, and are oriented at moderately oblique 

 angles in a ventro-dorsal plane. In other species with more flattened heads, the 

 suspensoria are elongated, and are angled obliquely in a much more latero-medial 

 plane. . , 



Opercular Series 



The opercle and interopercle of ageneiosids have a relatively primitive 

 shape. Both bones are very cancellous. The opercle is moderately large and 

 broadly triangular (Fig. 11). The interopercle is slightly flared posteriorly, as in 



