154 Memoir Sears Foundation for Marine Research 



6 b. Distance of dorsal origin from tip of snout about twice the distance 



of dorsal origin from caudal base; gill rakers long, slender, about 33 



on lower limb of first arch in young, probably more in adults; anal 



with about 25 rays. Hildebrandichthys Schultz 1949, p. 230. 



2 b. Teeth in jaws, especially the lower ones, notably large, usually unequal in 



size. Lycengraulis Giinther 1868, p. 233. 



I b. Gill covers broadly connected across isthmus by a thin membrane (easily torn). 



Cetengraulis Giinther 1868, p. 245. 



Explanation of Measurements and Counts for EngrauJidae. 



Total length : from tip of snout to vertical at rearmost point of longest caudal 

 lobe. 



Standard length : from tip of snout to base of caudal fin, i. e. to the last vertebra, 

 as nearly as can be determined without dissection. 



Caudal peduncle: least depth unless otherwise noted. 



Length of head: from tip of snout to most distal part of bony opercular margin, 

 regardless of whether the straight line between these points is horizontal or oblique. 



Depth of head: vertical distance at joint of mandible. 



Postorbital length : from posterior rim of eye to most distal part of bony oper- 

 cular margin. 



Maxillary: from its anterior embedded end (located by touch) to its posterior 

 extremity. 



Cheek (smooth bone below and behind eye): distance from rim of eye to its 

 distal point; the degree of its posterior angle determined by a protractor. 



Dorsal and Anal fins: the counts include all rays, whether simple and un- 

 segmented, simple and segmented, or branched; the last ray of the anal, even though 

 split to the base, was counted as one unless definitely separated at base. 



Length of pectoral: from base of upper ray to tip of longest ray. 



Pectoral axillary scale: distance from base of upper ray of pectoral to tip of 

 the modified scale or process. 



Splint: adhering to first ray of pectoral; not considered distinct and not counted. 



Scales or Scale pockets: counted along the side from the upper anterior angle 

 of the gill opening to the base of the caudal; as the scales are nearly always lost in 

 preserved specimens, they are generally not shown in the illustrations, except for a 

 small patch. 



Gill rakers: the counts are given as a formula, e.g. 12—16+ 15-18 (as for Anchoa 

 spinifer'), meaning a range of 12—16 rakers on the upper limb of the first branchial 

 arch and 15-18 on the lower limb. The counts include those rudiments, if present, 

 that have a free tip but not those that are mere tubercles. The gill raker at the angle of 

 the first arch generally has a plainly visible root, extending either upward or down- 

 ward; if the root was directed upward, the raker was included with the upper limb 



