CYTTOMORPIIS. 
305 
with only few rays. As yet we know nothing, it is 
true, of the changes of development through which 
the Cyttomorph fishes pass during early youth 0 , and 
which would probably give the safest clue to the 
solution of the question as to their right place 
in the system. But the points we have mentioned 
above, defend the position they occupy in the present 
work. 
The series, which derives its name from one of 
the genera, Cyttus , is composed of one, perhaps two 6 , 
families, containing more or less pronounced deep-sea 
or pelagic fishes. 
Fam. CYTTIDjE. 
No branched rays in the dorsal, anal or pectoral fins. The last-mentioned, fins with few rays. Ventral fins with 
one spinous ray and more than five soft rays. Basal bones of the pectoral fins flat , but very narrow in the 
middle. Branched rays of the caudal fin few. Jaws and vomer furnished with comparatively weak, car di form 
teeth. Mouth capable of extensive protrusion. Eyes lateral. Gill-openings large. Brancliiostegal rays 7 or 8. 
Bseudobranchice present. 
The family is not large, though its range extends 
over the basins both of the Atlantic and the Pacific. 
The 8 or 10 species it contains, may easily be included 
in two genera, Zeus and Cyttus, the latter without true 
(spinous) plates, with the spinous rays of the dorsal fin 
flexible at the tip, the fin being also without free, mem- 
branous appendages, and with only 2 spinous rays in 
the anal fin, but 8 brancliiostegal rays. 
Genus ZEUS. 
Scales small or wanting. Spinous plates, with one or two spines, along the whole or a part of the base of the 
dorsal fins, as well as of the ventral edge and the base of the ami fin. The two dorsal fins contiguous or co- 
alesced, the anterior containing 9 or 10 strong, pungent spinous rays, and with the membrane between these rays 
elongated into long filaments or fiat, clavate lobes. Anal fin with 3 or 4 strong spinous rays in front , which 
sometimes form a distinct lobe, representing an anterior anal fin. Brancliiostegal rays 7. Air-bladder large 
and the pyloric appendages very numerous. Coloration with a more or less pronounced, silvery lustre, marked with 
black, either in the form of large, irregular , transverse or wavy, cloudy spots or of a sharply defined, round 
spot at the middle of the sides. 
From this genus Gill'', by the establishment of 
the genus Zenoides, has separated the species which 
have only three spinous rays in the anal fin, but are 
furnished with spinous plates even along the base of 
the spinous-rayed part of the dorsal fin, leaving the 
other species to form the true genus Zeus. All these 
species, however, are so nearly allied — only 5 or 6 
can be distinguished with certainty — that it is im- 
possible to recognise these divisions as more than 
subgenera. Only the latter division is represented 
in the Scandinavian fauna, and that by only one 
species. 
“ As we know, L. Agassiz stated positively that Argyropelecus hemigymnus, a Mediterranean form of the family Sternoptycliidai, was 
a juvenile form of Zeus paper (Ann. Sc. Nat., ser. 5, vol. 3 (1865), p. 56), and Low had already proposed (Proc. Zool. Soc. London 1843, 
p. 85) to range the genus Sternoptyx beside Zeus. The observation has not been confirmed, however, and Kner has justly remarked (Verb. 
Zool. Bot. Gesellsch. Wien, XV (1865), p. 288) its great improbability, though the resemblance to the Sternoptychidce is worthy of mention. 
h If the family Oreosomatidce proves, on more minute investigation, really to belong to this series. In Oreosoma, according to Cuv., 
Val., the pectoral fins contain numerous branched rays, the palatine teeth are present and the ventral fins contain only 5 soft rays. 
c Proc. Acad. Nat. Sc. Philad. 1862, p. 126. 
Scandinavian Fishes. 
39 
