CY'rr()M(iiij'ii,s. 



305 



with only few rays. As yet we know iiothiii<j;', it is 

 tnic, of the elianges of developirieiit ihfouiiii which 

 the ( 'yttonioi'])!! fishes ]);iss (hiriiii;- eni'lv Nouth", niul 

 which \\()ul(l |)i'ol)!il)ly <ji\e the stifest clue to tlu; 

 solution of the i|uestion ;is 1o their I'iaiit place 

 in tlie system. l)ut the points we htivc! nientioned 



above, defend the position they oceui)y in the present 

 work. 



The series, which derives its niune from one of 

 th(! genera, Ci/tfus, is composed of one, perhaps two'', 

 families, containing more or less pronoiuiced deep-sea 

 or pelagic fishes. 



Fam CYTTIDtE. 



X(> lirai/clied rai/s in flic dm-sdl, iiikiI <ir pectoi'dl ,fiiis. Tlic hisl-mentiofied fins iritli fcir /w/.s. Ventral Jins irlth 

 our spinous ru[i and niorc IIkdi five soft ra/js. Basal liones of the j)ectoi-((l fins flat, Ijiit rcri/ nary<nr in the 

 middle. Branched rays of the eaiid(d fin feir. -fairs and vomer furnished with comparatively ireak, eardiform 

 teeth. Mouth capat)le of extensive protrusion. Eyes lateral, (lilt-openings lari/e. Branchiostegal rays 7 or 8. 



FseudobraneJrm present. 



The familj' is not large, though its range extends 1 (spinous) plates, with the spinous rays of the dorsal fin 

 over the basins both of the Atlantic and the Pacific. flexiljle at the tip, the fin being also without free, mem- 



The 8 or 10 species it contains, may easily be included 

 in two genera, Zeus and Cyttus, the latter without true 



branous appendages, and with only 2 spinous raj^s in 

 the anal fin, l)ut 8 branchiostegal rays. 



Genus ZEUS. 



Scales small or irantiny. Spinous plates, with one or tiro 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 anal fin. The two dorsal fins contiguous or co- 

 aleseent, the anterior containing 9 or 10 strong, pungent sinnous rays, and irith the membrane betiveen these rays 

 elongated into long filaments or fiat, clavate lobes. Anal fin with S or 4 strong spinous rays in front, which 

 sometimes form a distinct lobe, representing an anterior anal fin. Branchiostegal rays 7. Air-bladder large 

 and the pyloric appendages very numerous. Coloration ivith a more or less pronounced, silvery lustre, marked with 

 black, either in the form of large, irregular, transverse or irary, rlmidy spots or of a sharply defined, round 



spot at the middle of tlie 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 

 tlie 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 (i 

 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 staled positively tliat Anji/ropelccitii hcmigyiiiiiiis, a Medilerraneaii form of the familj- Sternnptychidie, was 

 a juvenile form of Zms faber (Ann. Sc. Nat., ser. 5, vol. .S (18(>u), p. 5(i), and Low had already proposed (Proc. Zool. Soc. London 1843, 

 p. 85) to range the genus ^teniopty.i- Ijeside Zeus. The observation has not been confirmed, however, and KfJEB has justly remarked (Verb. 

 Zool. Bof. (Sesellsch. Wien, XV (18G5), p. 288) its great improbal)ility, though the resemblance to the SternoptyMdm is worthy of mention. 



'' If the family Oreosomatidw proves, on more minute investigation, really to belong to this series. In Oreosoma, according to Cut., 

 V.M,., the pectoral fins contain numerous branched rays, the palatine teeth are present and the ventral fins contain only 5 soft rays. 



•- Proc. Acad. Nat. Sc. Philad. 1862, p. 126. 



39 



Scandinavioft Fishes. 



