of upper jaw contained in length of mandible 

 1.04 to 1.13 times. Interorbital region flattened. 

 A band of small toothlike irregularities on pala- 

 tines of largest specimen (FMNH 66924, 108 

 mm. SL), teeth not apparent on palatines of 

 other specimens; teeth not apparent on vomer 

 or pterygoids. Preopercle almost smooth or with 

 small serrae (particularly in region of angle) ; 

 rarely with a spinelike process at angle. Anterior 

 part of snout, most of gular region, and most of 

 branchiostegal membranes without scales ; often 

 one to several scales present in midline of an- 

 terior part of gular region ; frequently one to 

 several scales present on the membrane cover- 

 ing the fourth branchiostegal ray. 



Counts 



Frequency distributions for the following 

 counts are given in tables 2, 3, and 4. Dorsal-fin 

 rays' IX or X, 9 or 10 (usually IX, 10). Anal- 

 fin rays III, 7 or 8 (usually 8). Pectoral-fin rays 

 16 or 17 (usually 16). Gill rakers 12 to 14 + 26 

 to 29— total 39 to 42. Pored lateral-line scales 45 

 or 46. Sum of total number of gill rakers on 

 anterior gill arch plus number of pored lateral- 

 line scales of individual specimens 84, 86, 88. 



Measurements 



Ranges of selected measurements are pre- 

 sented in percentage of standard length followed 



'One specimen (UMML 11050, 58 mm. SL) has 10 dorsal spines. 

 The ninth spine in the series appears lo be intercalated between what 

 would normally be the last two dorsal spines. It is shorter than either 

 the spine anterior or posterior to it and arises abnormally close to the 

 last spine. 



by the value for the holotype of S. octoactinus 

 in parentheses. Length of head 33.9 to 36.3 

 (34.6). Depth of head 27.4 to 30.9 (29.0). 

 Length of snout 6.4 to 8.6 (7.6). Horizontal 

 diameter of fleshy orbit 12.1 to 15.4 (14.4). 

 Width of suborbital 0.6 to 1.0 (0.8). Height of 

 cheek 5.6 to 8.0 (7.3). Length of upper jaw 14.4 

 to 16.5 (16.1). Length of mandible 16.0 to 18.4 

 (18.0). Width of bony interorbital 9.0 to 10.5 

 (9.9). Depth of body 33.4 to 36.0 (34.8). Least 

 depth of caudal peduncle 12.0 to 13.2 (12.8). 

 Pectoral fin usually reaching a vertical through 

 base of third or fourth dorsal soft ray ; length of» 

 longer pectoral fin 28.3 to >30.9 (30.5). Pelvic 

 fin usually reaching anal fin ; first pelvic soft ray 

 not greatly produced. Length of longer pelvic 

 fin ca. 25.8 to ca. 27.9 (ca. 25.8) . Length of base 

 of anal fin 16.5 to 18.8 (18.4). Length of de- 

 pressed anal fin 28.5 to 32.3 (30.9). Lengths of 

 dorsal spines: first 6.1 to 7.8 (>6.3), second 

 10.1 to 11.5 (10.7), third 12.8 to 14.7 (>13.1), 

 fourth 13.8 to 16.5 (>15.6), longest (fifth, 

 sixth, or seventh — most frequently the fifth) 

 15.4 to 18.4 (16.6), last 14.1 to 16.4 (15.2). 

 Lengths of anal spines: first 7.0 to 9.1 (7.3), 

 second 13.0 to 14.9 (14.4), third 14.9 to 18.0 

 (16.4). Caudal fin deeply forked, the lobes ap- 

 parently never greatly produced (however, 

 caudal fin damaged on most specimens) . Length 

 of upper lobe of caudal fin ca. 38.6 to >42.0 (ca. 

 41.4) . Length of lower lobe of caudal fin ca. 37.2 

 to 39.1 (ca. 37.2). 



FiGVRE 5.— Kolotype of Sympkysanodon octoactiyiiis (USNM 204084, formerly UMML 20775), 



79 mm. SL. 



REVISION OF THE GENUS SYMPHYSANODON 



343 



