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and M'lntosh-Prince's figures; i" judge from my studios of these stages in the 

 development of the fish they are pretty good (particularly the plaice and the flounder . 



One might think, if it is possible to know the young fishes of the various 

 species when they have just come out of the egg, then it must be still easier 

 to know them .at the later stages of their lives, and this may be true also; but 

 the fry changes so much that different features must he used to distinguish one 

 species from the other at the different statics of their lives, as the earliest features 

 disappear to give room for others. It is just as necessary, therefore, to know 

 these other characteristic features in order to recognize the young ones at their 

 later stages. — 



Considerable materials have been collected of young 'plaice, flounders, and 

 common dabs, but while the two former species have been gathered in all size- 

 following immediately after the pelagic stage, i. e. plaice which in <>nr sens arc 

 c 10 mm long, and flounders which arc 8 mnl and upwards, I do not know 

 the young common dabs till they are 12 — 13 mm long, caught in November, conse- 

 quently no short time after the spawning-period. 



The materials I have collected contain, on the whole, proportionally little 

 only of the pelagic stages, caught in open nature, so that I must put off any 

 closer account of these till more comprehensive materials have been col- 

 lected. In the mean time I shall say here already, that while the pelagic stage 

 of the plaice in our seas is generally ended with a length of c. 10 — ll mm , 

 that of the flounder with c. 8 mm , the pelagic stage of the common drib, though 

 it belongs to a smaller species, does not seem to he at an end till the fish has 

 reached a length of 12 — IS"""; at any rate I have found a little pelagic young 

 flat-fish which by the number of its fin-rays, as well as by commencing pig- 

 menting and the form of its mouth, must be determined as a common dab. 

 It was about 1 :->'»'" long. The specimen was caught at Endelave in July 93. 

 The wandering of the eye was not yet ended, and the specimen no doubt lived 

 in the water, not on the bottom. The slight pigmenting, decidedly, suggested 

 the same. — The common dab then seems in this respect to form a transition 

 to the pole (lrih (PI. cynoglossus), where we find a still larger pelagic stage, viz. 

 over 14 inni (M'Intosh). The bottom stages of both these fishes (the youngest fish), more- 

 over, agree in living only on the deeper water never near the shore as the young 

 plaice and flounders. 



The expression bottom stage, used of the young flat-fishes, means here the 

 stage at which the fry has ceased its pelagic life, and lives on the bottom like the 

 grown-up fish. The whole organisation of the young fish is changed at the same 

 time, and true tin-rays are developed in the pectorals, the last of all the fins 

 which get true fin-rays, at about the same time as the life on the bottom is com- 

 mencing. — 



The flounder is found on the sands immediately on the shore, represented 

 by specimens as small as 8 mm in length (plate II, fig. 12). The smallest are very 

 longish, and may be said almost to be just passing into the pelagic stage. 

 The fins, however, are all present, the median ones evidently w'th at leasl 



