23 289 



The clavicular aixh consists of 3 bones, a supraclavicle being present. 



The posttemporal (PI. I, fig. 5 pt) is suturally united to the skull (vide supra); 

 its outer margin is sculptured, with granules (F. tabacaria) or spines (F. petimba, 

 depressa); about midway between the occipital suture and the posterior end the 

 inner face shows a knob (PI. I, fig. 7 k) or rugosity for muscular attachment and 

 for a strong ligament, going to the front part of the first vertebra, corresponding 

 to the bony fork described in Aiilostoma; the ligament passing from the hind end 

 of the posttemporal to the anterior corner of the transverse process of the second 

 vertebra is also found in Fistularia. The supraclavicle is short; it has a shallow 

 concavity at the upper end for articulation with the posttemporal, and the lower 

 end covers part of the outside of the clavicle. 



The part of the clavicle (fig. 9, cl) corresponding to the sculptured plate in 

 Aulostoma is small (just observable through the skin, but hidden below the oper- 

 cular membrane); under its upper posterior corner the clavicle carries the long 

 postclavicle (pel), which broadens behind into a plate, partly sculptured on its 

 outer face and more or less visible through the skin. Distally the clavicle bifur- 

 cates into an outer (anterior) (o) and an inner (posterior) (i) branch; along the in- 

 side of the clavicle and that of its inner branch is attached the scapular arch. 



The latter consists as usually of the scapula (sc) and the coracoid (co). The 

 first encloses the wide scapular foramen; but the part encircling the anterior 

 border of the foramen is only very thin cartilage (easily lost in drying, probably, 

 therefore, overlooked by Starks). The inferior margin of the coracoid expands 

 into a large plate, broadening behind the pectoral fin, the outer face being to a 

 great extent sculptured and visible through the skin; anteriorly it combines with 

 both branches of the clavicle, ending in front of the outer (anterior) branch of the 

 latter as a flat, pointed process, to which the urohyal is fastened. The part 

 between the clavicular branches unites with its fellow from the opposite side, a 

 particularly firm connection being established at the level of the inner (posterior) 

 branch (fig. 8). 



The four pterygials (ba) are well developed, similar to those in Aulostoma; 

 the uppermost, rather small one is fastened to the scapula, the remaining three 

 are larger, laterally compressed and somewhat hour-glass-shaped in outline '\ 



The pectoral fin has 15 — 16 soft unbranched rays, the uppermost rudi- 

 mentary; the upper (4—5) rays are not jointed, as the rest are. 



The pelvic bones, abdominal in position, are still farther apart from each 

 other than in Aulostoma. Each is a flat bone with the exterior margin rounded in 

 outline, the inferior straight. There are 6 ventral fin rays, the outer unbranched 

 but jointed like the rest, which all are distally branched. 



Visceral anatomy. 



There are four complete gills and a large pseudobranchia, a slit between the 

 fourth gill-arch and the lower pharyngeals. 



