1026 



h)iv^ the corresponding percentages were respectively 

 4"8 and 10. In the males the former percentage varied 

 l)etween 3'0 and 3'7, in the females between 3"8 and 

 4'5. The latter percentage varied in the males between 

 7 '5 and 8'G, in the females between 9 and 10'9. That 

 this sexual difference — as it apjtears in the above 

 measurements — is fully constant, enabling us in every 

 instance to distinguish between males and females, is 

 hardly probable, for it coincides with a marked altera- 

 tion of growth; but it would seem at least to show 

 that the males retain the characters of youth longer 

 than the females". 



The thick and tough skin completely envelops even 

 the tins, but owing to the underlayer of lax connective 



SCANDINAVIAN FISIIKS. 



cial scales 



t 



Fig. 276. Scale of Anijiiilln riilgai-is. About 23 times the natural size. 



tissue and fat is so loosely attached — as every kit- 

 chenmaid should know — that it can easil}' be stripped 

 off entire. The copious .slime tiiat covers it has ren- 

 dered the Eel's slipperiness proverbial; and the system 

 of the lateral line is \vell developed. The lateral line 

 itself, which is straight, lying about half-way up the 

 sides, in front somewhat higher, so as to meet the 

 temples, is made ii]i of c()ni])ai';itively scattered })ores, 

 on the tail often indistinct, and not su])])orted by spe- 



)ut Msiiallv marked otl' b\- their light hue 

 from the gi-ound-coloration. The ce])halic system of 

 the; lateral line shows a transverse row of pores across 

 the top of the head behind the ej^es, from which they 

 are sepai-ated h\ a distance about equal to the length 

 of the snout; and on each side runs a i-ow, usually 

 containing tliree distinct pores, straigiit forward from 

 the transverse row, towards the su])eri(jr margin of the 

 eyes, but not extending half-way thither. More distinct 

 are the pores on the snout, one row on the turbinal 

 bones and the suborliital ring, another on each half 

 of the mandible. The scales, which are entirely im- 

 mersed in the skin, are thin, flexible, and of a ])ro- 

 longated elliptical shape, somewhat constricted at the 

 middle of their length, which is aliout half the dia- 

 meter of the eyes. On the .sides of tlie liody their 

 arrangement is such that a certain number, usually 

 3 — .5, lie beside and contiguous to each other, obliquely 

 across the longitudinal direclion of the body, and on 

 each side of this grotip lie others, the scales of which 

 are set at about right angles to the former. Or each 

 grou]) may be longer, containing u]) to a score of 

 scales, and tbrming a straight or curved row. ())• the 

 scales may be iuxta]>osited one l)y one, in the said 

 zigzag arrangement, (hi the belly the scales are more 

 scattered, and more nearly apjjroach to the longitudinal 

 direction of the body. The texture of the scales is 

 highly characteristic. When slightly magnified, the 

 entire surface seems to be composed (jf dense strings 

 of lustrous beads, all parallel to the margin. When 

 the scale is more powerfidly magnified (flg. 276), this 

 conformation dissolves into a honeycombed network, 

 due to the union of the concentric stria^ (ridges) round 

 the elongated, central nucleus by radiating ridges of 

 equal elevation. 



The coloration of the Eel varies with age, the 

 season (jf the veaf, the haunt of the fish, and jtartly 

 too with its sex. The dorsal side is of a lighter or 

 darker, greenish or grayish colour, the \entral yellow 

 or white; the middle of the sides has a bronze lustre 

 of varying intensit\\ The colour of the fins usually 

 resend)les that of the Ijack, except in the case of the 



" How futile it is to nly on the external sexual eharaeters liitherlo assisue.l in literature to tlie Eel. is most elearly sliown by tlie 

 conflieting results at which different writers have arrived, .\ccording to ,1acoby {Fisrhf. Comacchio. Berlin 1880, p. 40) tlie males have 

 pointed snouts. From his measurements (p. 41) it appears that the breadth of tlie snout at the nasal duets — (1 assume that "Breite der 

 Schnauzenspitse zwischen den Nasaltuben" nnist be taken in this sense, for "between" the nasal tubes I have never found the distance so 

 great) — measured in 8 males (319 — 480 mm. long) less, in 8 females (313 — 480 mm. long) more, than 12 % of the length of the head. 

 According to LiLUEDORQ (,Sv., Novg. Fisk., vol. Ill, p. 382) the niale.s most eommonly have blunt, "sometimes pointed" snouts. 



