MLLLIDAE OF THE WESTERN NORTH ATLANTIC 



439 



after 16 mm. The numbers of fin rays are plotted 

 a<r;unst size in table i), p. 434. 



Segmentation began with tlie third ray at ap- 

 [>n).\imately 25 mm., then proceeded ventrally 

 tiu'oujrh the rays until the first ray and tlie last 

 ray segmented at approximately 47 mm. 



A 25-mm. specimen liad no branched rays, but 

 at. 27 mm. there were four branched rays, the 

 fourth through the seventii. At 47 mm. all except 

 tiie first two rays were branched — the first two 

 rays never branch. 



Pelvic. — Segmentation apparently occurred si- 

 multaneously in all five soft rays. There was no 

 segmentation in any of the specimens examined 

 up to 14 mm., but specimens over 14.5 mm. had 

 all pelvic soft rays segmented. 



Branching, which had not occurred through 18.7 

 mm., was complete at 25 mm. 



Anal. — All adult specimens examined had one 

 spine, one unbranched ray, and six branched rays. 

 Segmentation began at approximately 14 mm. and 

 was complete by 16 mm. 



The smallest specimen, 8.2 mm., had the last ray 

 branched. Additional branching was not evident 

 until 17 mm. and was complete at 21 mm. 



Caudal. — There were 15 principal rays on all 

 specimens examined. All principal rays were seg- 

 mented at 9.3 mm. 



The innermost rays were the first to branch, be- 

 ginning at about 14 mm., and branching was com- 

 plete on all specimens over 18.7 mm. 



Between 14.5 and 42 mm. the number of sec- 

 ondary rays was 9 or 10 in the dorsal lobe and 8 

 to 10 in the ventral lobe. Xine is the usual number 

 for each lobe. After 42 nmi. the anterior rays 

 were overgrown by tissue and scales and could not 

 be counted. 



At 9 mm. the five dorsal and four ventral sec- 

 ondary rays were unsegmented. On a stained 

 10.9-mm. specimen, there were eight unsegmented 

 secondary rays in each lobe. At 14.5 mm. there 

 were 18 secondary rays, and the first ray adjacent 

 to the principal rays in both dorsal and ventral 

 lobes had segmented. The secondary ray second 

 from the principal caudal rays in each lobe was 

 not segmented in fish less than about 45 mm. A 

 cleared and stained 154.0-mm. adult had segmenta- 

 tion in only the first two secondaries adjacent to 

 the principal rays in each lobe. 



Gill rakers 



I'otal and lower limb. — Both total number of 

 gill rakers (16-23) and numbers of gill rakers on 

 the lower limb (ll-Ki, exclusive of the one at the 

 angle of the arch) were counted on 48 specimens, 

 ranging in size from 9 to 199 mm. Below 9 mm. 

 counts were not reliable. Counts are plotted 

 against size in tables 10 and 11, pp. 434, 435. In 

 both instances there was an increase in average 

 number of gill rakers with increase in size up to 50 

 mm., then the average number decreased with fur- 

 ther increase in size of specimens (decrease was in 

 the number of rudiments as they appeared to be 

 overgrown by tissue). 



Ceratobranchlal bone. — Counted on 10 speci- 

 mens (28.6 to 138.8 mm.), of which 1 had 9 gill 

 rakers, 1 had 11, and the others had 10. 



Teeth 



Upper jaw. — Contrary to generic descriptions 

 (based on adult specimens), M. auratus less than 

 50 mm. do have visible teeth in the upper jaw. 

 Consequently, keys to the Mullidae which use the 

 teeth to separate the genera are confusing when 

 applied to specimens smaller than 50 nmi., and the 

 possibility exists that M. auratas may be involved. 



The genus Mullus was first described by Lin- 

 naeus in the 10th edition of "Systema Xaturae"' 

 (1758), but thei'e was no mention of the teeth 

 either in this or the 12th edition (1766). In the 

 13th edition (Linnaeus and Gmelin, 1789) the 

 teeth were first mentioned (translation) — ". . . 

 mandibulae and palate armed with small 

 teeth . . . ." Whether "mandibulae" refers to both 

 upper and lower jaws, I can't saj'. Turton (1806) 

 interpreted the word mandibulae as "jaws." Since 

 Linnaeus, Mullus has been described in the litera- 

 ture as being without teeth in the upper jaw. 

 GUnther (1859) said of the teeth of the genus 

 Mullus, ". . . none in upper jaw," and Jordan and 

 Evermann (1896) used the same words, ". . . none 

 in upper jaw . . . ." However, in the original de- 

 scription of M. auratus by Jordan and Gilbert 

 ( 1882) , which named M. auratun as a subspecies of 

 Mullus barbatu.^. tlie authors stated, "Teeth . . . 

 on upper jaw obsolete . . . ." Examination of the 

 juveniles of the species has shown that this last 

 observation by Jordan and (iilbeit was accurate. 



Small canine teeth were apparent on the ui)per 

 jaw of M. aurafus of 12 mm. A 21-mm. specimen 

 liad 3 or 4 teeth on each side of the upper jaw, and 



