546 



.SCAN]>1XAVIAN FISHES. 



are wide, fov the (lennnl fold fovnied by the inferior 

 union of the branchiostegal membranes is free from the 

 isthmus forward to the anterior end of the hyoid lione, 

 and tlie upper corners of the gill- openings lie far up 

 the sides, on about a level Avith the upper margin of the 

 ('\o>i. The tongue is broad and thick, with the free 

 margin and tip thin. The pointed and curved jaw-teeth 

 form a card in most cases distinct, on the front part of 

 the intermaxillary bones; but this card grows consider- 

 ably narrower behind, and sometimes, in old specimens, 

 even at the very front of the maxillaries, we find only 

 two or three rows within the outermost row, which is 

 made u\) of larger but more scattered teeth. In the 

 lower jaw tlie innermost row is composed of larger teeth, 

 and in fi'ont of this row we generally find only one row 

 of smaller teeth. The card of teeth on the head of the 

 vomer contains small teeth, which gradually disappear 

 with age. In young specimens this card is crescent- 

 shaped, convex in front, or triangular, with several rows 

 of teeth, but in old specimens there are only one or t\vo 

 rows of vomerine teeth. The l)readth of the card is at 

 most about ^Z,, and eventually no more than Vj, of the 

 longitudinal diameter of the eye. The pointed, conical, 

 ]jharyngeal teeth together form a l)road, oval card on 

 the upper pharyngeals on each side; and the lower 

 pharyngeals, which are scaphoid in shape, and somewhat 

 curved at the middle, the breadth being '/^ of the length, 

 are furnished Avith 5 or 6 rows of similar teeth. The 

 gill-rakers ai'e short and scattered, like tubercles, the 

 first bi'aiichial arch being furnished with 8 — 10 pairs. 

 During life tlie wliole of the l)ranrhial cavity and the 

 cavity of the mouth with the tongue ai'e bluish black. 

 The first dorsal fin — which in this germs consists 

 of about 50 free, filamentous rays, which vibrate during 

 life, and are without interspinal bones — is distinguished 

 in the Four-Bearded Rockling by the remarkable length 

 of the first ray, which in the females measures about 

 '., of the length of the head, in the males up to at 

 least 87 % thereof. In tlie males its tip, when laid back, 

 may thus extend some way behind the beginning of the 

 second dorsal fin. The distance between the liegiiniing 

 of tlie first dorsal tin and the tip of the snout is 15 — 

 1 7 % of the length of the body, and the length of its 

 1)ase measures about 8' ^ — 10 % of this length or ■ii)\'^ 

 — 55 % of that of tlie head. Tliis tin is always se])a- 

 rated by a distinct interval fVoin the second dorsal fin, 

 which begins at a distance from the tip of the snout 

 that measures about •id' ., — 21) % of the length of the 



body. The base of the latter fin extends nearly to the 

 caudal tin, and measures about 57\', — 59% of the len<>t]i 

 of the body. All the rays of this fin, except the first 

 one, are branched at the tip, the first 4 — 6 gradually, 

 increasing in length and the last 4 or 5 growing gra- 

 dually shorter. The other rays are of fairly uniform 

 length, l^ut somewhat longer in the posterior part of the 

 fin, the length of the longest ray varying between about 

 7^/2 and 9 ?fv of that of the bod}'. The caudal fin is 

 sharply rounded when expanded, lanceolate when folded. 

 The anal fin resembles the second dorsal, l)ut is much 

 shorter and distinctly lower. It begins at a distance from 

 the tip of the snout of about 41 % (-38 — 43 %), its base 

 measures about 45 % (43\'2— 49 %), and its longest ray 

 about 6 '/a ?6 (6 — 7 %) of the length of the body. 



The pectoral fins are oval and obtusely pointed, 

 with the middle rays longest and the first two simple. 

 They are fairly long, measuring about 13 % (H^s — 16 

 %) of the length of the body. The ventral fins are set 

 far apart, almost below the beginning of the first dorsal 

 fin or a little further forward, at a distance from the 

 beginning of the anal fin that measures about 2IV2 — 

 26 ?6 of the length of the body. The first two rays, 

 sometimes the first three, are free at the tip. Tlie length 

 of these fins is about 8 % (7 — 10 %) of that of the body. 



The anal aperture, with a small anal papilla behind 

 it, lies just in front of the beginning of the anal fin. 



The scales are small, but densely imbricated, and 

 extend — growing smaller and smaller forAvards and out-' 

 wards — over the whole of the head, leaving oiih' the 

 branchiostegal meml)rane and the li|)S naked, and over 

 the entire membi'ane of the second dorsal and the caudal 

 fins, as well as over the hind part of the memlirane of 

 the anal fin. The outer surface of the pectoral fins is 

 also clothed with scales to an extent of about one-third; 

 but the ventral fins are naked. The lateral line is some- 

 times scarcely distinguishable: in the original of our 

 figure, a female, no lateral line could be traced while 

 the specimen was fresh. It runs from the upper corner 

 of tlie gill-opening, parallel to the dorsal edge, until it 

 reaches the perpendicular from about the vent. At 

 this point it descends, at first not (|uite to the middle 

 of the sides of the tail, but afterwards coming nearer 

 and nearer this position, and advances straight to the 

 middle of the base of the caudal fin. Its scattered 

 pores, about 30 in nuniher, are either simple or some- 

 times, in its anterior part, ramified in the form of a 

 cross or a rosette. 



