COMMON DAB. 



389 



scales may be found on the liiiul juirt of the upper jaw 

 and of tlie branches of the lower jaw. Most of the tin- 

 rays, \vith the exception of llie very first and last rays 

 of the dorsal and anal tins, and the posterior rays of the 

 pectoral and ventral fins, are each furnished -with a row 

 of scales. On the blind side, however, the operculum, 

 preoperculum and interoperculnm are for the most part 

 naked, as well as the whole of the jaws, the snout, and 

 the nasal region up to the begiiming of the dorsal tin. 

 Most of the fin-rays, too, on this side are without scales, 

 witli the exception of the caudal fin and the middle part 

 of the dorsal and anal tins, where there is one row 

 of scales on the inner (proximal) part of each of the 

 rays. On this side the ctenoid scales of the body are 

 set in patches along the dorsal and ventral margins and 

 on each side of the lateral line. 



The coloration of the eye side is yellowish brown, 

 with small, dark or brownish, sometimes reddish spots. 



It may be more or less dark, and fades after death, 

 when the spots, too, grow indistinct. On the coast of 

 Bohusliln, according to Mr. C. A. Hansson", the fol- 



lowing coJour-varieties occur 



"«, the coloured side dark grayish brown, entirely 



undiversified ; 

 ("}, the coloured side light brown, with more less nu- 

 merous, small yellowish spots with a dash of red. 

 ;', the coloured side clay-gray, shading into brown and 

 marked with small, more or less gi-eenish spots. 

 "It is stated that variety cc occurs on a hard, 

 clayey bottom. />' is the commonest, and occurs both 

 on sandy and muddy bottoms, while /, on the other hand, 

 seems to keep to a sandy bottom. Intermediate forms 

 are found, however, between all three varieties." 



The changes of growth in this species may serve as 

 an expression of those of the Flounders in general. The 

 iTQOst important of them are given in the appended table: 



PleuronecUs limanda. 



From BohuslSn. Most of the measurements 

 siven by ScNnF.VAI.r.. 



From Cim- 

 brisbamn 

 (Scania). 



From 



Wisbv. 



Sex 



Length of the body to the end of the caudal fin in millimetres . 



Length of the head in % of the length of the body to the end of the caudal fin 



»» •? ,» ;» - — — 55 J) »• ?. V ;> », 5, !, J) Dase 



Greatest depth of the body _. „ ,, „ „ „ „ „ ,, ., „ end 



J, i» ?i ?» ** jj i> )i '1 ', 1, M ,» 1* " base 



^cast „ „ „ „ „ ,, „ „ „ „ ,, ,, „ „ end ,, 



Longitudinal diam. of the eyes ,, ,, „ ,, 



Postorbital purt of the head „ „ ,, ., 



Length of the ri!;ht pectoral fin ,, ,, ,, ., 



,, „ ., ventral ,, , ., ,, ,, 



„ ,, M ., Ijranch of the lower jaw ., ,, „ ,, „ ., ,, 



.. .. ., .. .. ,, „ „ head 



., „ left ., ,, „ ., .. ., „ „ ., ., ,. „ body to the end of the caudal fin 



., ., ., ,, ., ., ., , , ,, head 



Distance between tlie anal fin and the tip of the snout in f^ of the Icagth of the body to the end of the caudal fin 

 Length of the ciindal rtn-_ „ „ „ ., 



?J !J ), 



243 

 19.0 

 23.0 

 38.7 

 48.0 



8.4 



4.1 



12.2 

 12.3 



7.7 

 7.3 



38.5 

 8.0 



41.7 



27.7 

 17.0 



9 

 229 

 20.7 

 25.2 



38.4 

 46.8 



8.3 



4.8 



12.4 

 13.5 



7.8 

 7.4 



35.9 



8.3 



40.0 

 30.6 

 17.9 



9 

 269 

 20.8 

 26.5 



40.9 



50.0 



9.0 



4.9 

 12.3 



13.0 



7.0 



7.6 



86.6 



8.3 



40.2 

 30.8 



18.2 



Ol/s. With regard to the young specimens in this table Sunde- 

 v.\Li. observes: In the fourth (94 mm. in length) the teeth are in form 

 and position like those of the largest specimen from Bohuslau. In the 

 two smallest (34 and 57 mm. in length) the scales are apparently 

 rather more rounded at the tip, and are furnished with fewer spines, 

 tlmn in the full-grown specimens. Their coloration is also fainter and 

 more transparent, with more distinct spots, than that of the others: 

 and tliey seem to belong to the fry of tlie previous j-ear. Young 

 specimens less than 25 mm. long are entirely transparent and colour- 

 less, with the exception of the eyes and the skeleton. 



In spite of the fact that these measurements cannot 

 be absolutely accurate, several of those in the first co- 



" By letter. 



' According to Kroyer the least deptli of the body is, as 

 given in out measurements. 



lumns being derived from the observations of different 

 persons, we may still draw from them the following 

 rules, subject, it is true, to individual variations that are 

 sometimes considerable. The relative length of the head 

 decreases with age, the greatest depth of the body in- 

 creases, while the least relative depth'' remains almost 

 the .same, the relative size of the eyes diminishes, as 

 well as the relative length of the postorbital part of the 

 head, which in older specimens, however, is remarkably 

 constant, but the length of the fins, on the other hand, 



a rule, nearly 10 % of the lengtli thereof, and thus greater than it is 



