53 



At the (iedser station, where we l'onud the eggs of the loug-rough dab, 

 the surface-water had thus the same temperature and sahuity as at the station in 

 the true Bahic (S. of Møen), whilst the bottom-water had the same temperature 

 and sahuity as at the station in the western Baltic (S. of Lolland). The eggs of 

 long-rough dab, found at the bottom in the salt water, must therefore be con- 

 sidered to have come with the bottom-curreut from the western Baltic. 



This explanation seems the more natural, as we found the loug-rough dab 

 in full process of spawuing in the western Baltic some days later: 



D. 23—3—04. Bagenkop (Longland) in N. E. to N., 3'/., miles, 1V!„ fm. Small Enghsh 

 trawl, 2 hauls of 30 minutes in all; 5 long i-oiigh dah, two of which were females, 33 and 38 em., 

 three males, 16, 20 and 25 cm. All these had running roe and milt. Many other fish were taken 

 at the same time. 



These were not the ouly spawniug long-rough dåbs we took in the western 

 Baltic in March 1904. We also found both females with running roe and males 

 with running milt to the west of Ærø. That we did not observe the eggs of 

 long-rough dab in the western Baltic in March, is probably due to the faet, pre- 

 viously mentioned, that few determinations of eggs were made during our March 

 cruise with the »Sallingsund;. 



The pelagic ijmmg uf the long-rough dah \\ere found in 1904 (see Tab. 3 B) 

 practically in all the Danish waters, where we sought for them in April, May and 

 June, but not in the Lim Fjord nor in the true Baltic. 



We found them the first time on April 13th in the Great Belt (see Tab. 1) 

 quite small, and all the young of long-rough dab we took in April, from the Great 

 Belt, Kattegat and Skager Rak were small. 



Asymmetricai young of the long-rough dab were met with late in May: 



D. 31—5—04. Light buoy on Tangen in S. S. E., 11 miles, 7 fm. (Tab. 1, Kattegat). 

 Young-fish trawl on I)locks on bottom, 10 minutes: 5 yotmg of long-rough dah, one was asymmetri- 

 cai with left eye on the ridge and right side more strongly pigmented than the left; it was 

 20 mm. long. 



Similar young of loug-rough dab were also got in the Skager Rak and 

 eastern Kattegat in the first days of June. 



The hnttom-stages were first taken on July 12th at Anholt in 21 fathoras 

 (see under dab). We took there 20 ,voung long-rough dab, 2 — 2^/2 cm., in a 20 

 minutes haul with the young-fish trawl on the bottom. This must be a good 

 locality, as, when we again fished here on July 28th, we got 34 young of long- 

 rough dab in the bottom-stage in 10 minutes. 



The same rule holds for the bottom-stages of the long-rough dab as for 

 those of'the dab, namely, that they live in deep water, but the young of the 

 long-rough dab seem to seek even deeper water than the dab young. In 1904 we 



