ESPECIALLY MYCTOPHOIDS 153 
Order MYCTOPHIFORMES 
Family SARDINIOIDIDAE nov. 
Diacnosis. Myctophiformes in which the post-temporal fossa is roofed ; the 
parietals meet in the mid-line anterior to the supraoccipital. Maxilla excluded 
from gape but expanded posteriorly with two supramaxillae. Premaxilla with long 
ascending process. Antorbital present, but no supraorbital. Both operculum and 
suboperculum large. Pelvics abdominal with a pelvic splint bone. Fulcral scales 
at base of tail. Vertebral elements incompletely fused. Ural vertebra 2 present 
as a terminal half-centrum. Scales cycloid or feebly ctenoid on body, also present 
on cheeks, operculum, skull-roof and posterior part of the maxilla. 
Genus SARDINIOIDES von der Marck, 1858 
1863 Leptosomus von der Marck : 49. 
1940 Cassandva White and Moy-Thomas: 102. 
DiaGnosis (emended). Sardinioididae in which the body is short and somewhat 
deepened. Vertebrae between 30 and 32. Branchiostegals about 9g in number. 
Pleural ribs delicate. Dorsal fin in the front half of the back, with between Io and 
18 rays. Pectorals small and delicate, situated on the flank. Gap present between 
hypurals 2 and 3 and a corresponding gap between the fin ray bases. Scales ctenoid 
in larger species, cycloid in smaller ones. 
TYPE SPECIES. Sardinioides monasteri (Agassiz). 
REMARKS. Hay (1903 : 424) and Arambourg (1954 : 60) have maintained that 
the correct name of this genus is Osmeroides Agassiz, on the grounds that Osmeroides 
monastert Agassiz is the type species of that genus. However the first publication 
of the name Osmerotdes in a binomial was as Osmeroides lewesiensis (Agassiz 1837, 
5 ; pls. 60b, c), an elopoid fish in no way related to Sardinioides, thus preceding the 
first use of Osmeroides monasteri (Agassiz 1839, 5 ; pl. 60d). Sardinioides is there- 
fore the valid generic name for the myctophiform fishes under consideration here. 
Sardinioides minimus (Agassiz) 
(Text-figs. 70-72) 
1839 Clupea minima Agassiz, 5: 2: pl. 61, fig. I. 
1844 Clupea minima Agassiz, 5; 2: 120. 
1866 Clupea minima Agassiz ; Pictet and Humbert : 65. 
1901 Leptosomus minimus (Agassiz) Woodward : 246. 
1903 Osmeroides pontivagus Hay : 424, pl. 33, figs. 1-4. 
DiAGnosis (emended). Sardinioides of standard length not exceeding 45 mm. 
Length of head with opercular apparatus just less than one-third of the standard 
length, and equal to the maximum depth of the body. Pectoral fin with 14 rays ; 
pelvic fin with 9 rays. Dorsal fin with 11 rays; anal fin with g rays. Four 
accessory radials in advance of the dorsal fin. Scales mainly cycloid, some feebly 
ctenoid. 
