SCANDINAVIAN FISHES. 
456 
Genus ZEUGOPTERUS. 
Jaw-teeth of uniform size ( no canines ), pointed , recurved , small , and set in a card on the front part of the inter- 
maxillary hones and of the lower jaw. Head of the vomer also furnished with small teeth , hut the palatine hones 
and tongue smooth. Lower pharyngeal teeth set in several rows (car di form). Most of the fin-rays branched. Bran- 
chiostegal membranes partially united below, hut further hack meeting in different planes , the one crossing the other. 
Brancliiostegal rays 7. Median wall of the branchial cavity pierced above the uroliyoid bone by a hole. Ventral 
fins united by the fin-membrane to the first ray of the anal fin. Scales on the eye side of the body ciliated at the 
hind margin , on the blind side smooth-margined ■ Anal 
anal fin and the tip of the snow 
Only one species of this genus is known, the sy- 
stematic significance of which in relation to the pre- 
ceding genera we have already touched upon. The 
characters on which the genus is based, are, however, 
of only secondary rank. In a young specimen, 12 7 2 
mm. long, which the writer took in a hoop-net at the 
surface, at about the middle of the west entrance of 
the English Channel, where there were 55 fathoms of 
water, and in which specimen the right eye had only 
just begun its passage under the free, projecting front 
part of the dorsal fin, the ventral fins are separated 
from the anal fin by an interval equal in length to 
spine and preanal spines wanting. Distance between the 
less than the length of the head. 
their own bases, and both the dorsal and the anal fins 
terminate posteriorly at the middle of the edges of the 
body. The independence of the genus has thus no more 
significance than that of a distinct stage — the most 
advanced of all — in the course of development that 
has started from an ancestral Bothoid type common to 
this genus and the preceding one. 
The genus was established in 1835 by Gottsche, 
but gained no further recognition until Steenstrup, who 
included in it the two preceding genera as well, thirty 
years after pointed out the characteristic breach in the 
wall between the two branchial cavities. 
MULLER'S TOPKNOT (sw. ludna ii varfven a or bebgiivarfven ■'). 
ZEUGOPTERUS PUNCTATUS. 
Plate XIX, fig. 2, and fig. 116. 
Greatest depth of the body more than 46 %>, total length of the head more than 26 %, length of the head behind 
the lower eye. more than 14 %, maxillary bones of both sides more than 10 %, branches of the lower jaw more 
than 12 %>, pectoral fin of the blind side more than 8 %, base of the dorsal fin ( measured in a straight line) more 
than 84 %, its greatest depth ( longest ray — about the 60th — 70th ) more than 11 %, base of the anal fin more than 
73 %, its greatest height ( longest ray — about the 40th — 47th) more than 11 %, distance between the anal fin and the 
tip of the snout less than 23 %, length of the middle rays of the caudal fin less than 13 %, greatest thickness of 
the body more than 7 %■ — in each case relatively to the length of the body. Length of the pectoral fin of the 
blind side less than 77 %, but more than 66 %, of that of the lower jaw on the same side , and the length of the 
middle caudal rays less than either the length of the lower jaw or half the length of the head. 
Least depth of the tail less than 16 % of the greatest depth of the body. 
R. hr. 7; D. 87 — 99 c ; A. 67— 75 P. sin. 11 1. 12, dextr. 
10 1. 11 (12); F. 6; C. 2 + 12 + 2"; Lin. tat. ca 200; Vert. 36 1.37. 
Syn. Pleuronectes punctatus, Bl., Naturg. Ansi. Fische, part. Ill, 
p. 31, tab. CLXXXIX; Walb., Ichth. Art., part. Ill, p. 
a Nilsson, 1. c. 
1 Malm, 1. c. 
c Sometimes 101, according to Day. 
d Sometimes 80 or even 89, according to Gottsche. 
" Or 1 + 14 + 1, or 2 + 13 + 1. 
116; Gthk (Rhombus), Cat. Brit. Mas., Fish., vol. IV, p. 
413; Coll. ( Zeugopterus ), Forh. Vid. Selsk. Christ. 1874, 
Tillsegsh., p. 139; Malm, Gbgs, Boh. Fn., p. 518; Winth., 
Naturh. Tidskr. Kbhvn, ser. 3, vol. XII, p. 38; Day, Fish. 
Gt. Brit., lrel. , vol. II, p. 18, tab. C; Coll., N. Mag. 
