. Bulletin of the British Museum (Natural History). Zoology . 170 P. J. P. WHITEHEAD. Fig. 65. Gillrakers and jaw teeth in Lycengraulis batesii. a. Syntype of Engraulis batesii, 192-0 mm , BMNH (1st arch). b. Surinam fish, 185-5 mm , RMNH 26295 (aU arches). c. Juvenile, 31-4 mm , RMNH 21490. d. Adult (as b above). Posterior border of gill opening evenly rounded. Isthmus silvery in some, taper- ing evenly forward to hind margin of branchiostegal membrane, the urohyal exposed before this but without ventral bulge. Branchiostegal membrane narrow, the longe
. Bulletin of the British Museum (Natural History). Zoology . 170 P. J. P. WHITEHEAD. Fig. 65. Gillrakers and jaw teeth in Lycengraulis batesii. a. Syntype of Engraulis batesii, 192-0 mm , BMNH (1st arch). b. Surinam fish, 185-5 mm , RMNH 26295 (aU arches). c. Juvenile, 31-4 mm , RMNH 21490. d. Adult (as b above). Posterior border of gill opening evenly rounded. Isthmus silvery in some, taper- ing evenly forward to hind margin of branchiostegal membrane, the urohyal exposed before this but without ventral bulge. Branchiostegal membrane narrow, the longest rays a little greater than snout length. Gillrakers short, stumpy, with a few short spines near the tip, the longest raker (at angle of arch) one-third of eye diameter or 0-66-075 pupil diameter, the rakers anterior to this on both upper and lower arches becoming progressively shorter until they are represented by mere stumps and finally small, flat discs (Figure 65b) ; rakers on subsequent arches even more degenerate, especially in larger fishes ; one to three very rudimentary gill- rakers on posterior face of 3rd epibranchial (none in some specimens). Pseudo- branch present, 0-80-1-00 eye diameter in length, about 15 filaments covered by thin layer of skin. Dorsal origin much nearer to caudal base than to snout or even eye, the distance behind the dorsal base often half that in front of it but rather variable ; dorsal origin nearer to caudal base than to snout tip by about 3-5 (small fishes) to 5 (large fishes) eye diameters ; base of fin invested in strong scaly sheath ; longest dorsal finrays just reaching to tip of last ray when fin depressed. Pectorals just reaching to pelvic base ; axillary scale present, two-thirds length of fin, triangular in cross- section and with fleshy margins anteriorly. Pelvic base nearer to pectoral base. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and
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