FISHERY BOARD FOR SCOTLAND. 



ON THE REPRODUCTIVE ORGANS OF SFARUS CENTROBON- 

 rt//S, Delaroche ; SPARVS CAA'THARUS. h.-, SE BASTES 

 MARIN US (L.); AND SEE AST ES BACTYLOPTERUS 

 (Delaroche) ; AND ON THE RIPE EGGS AND LARV^ 

 OF SPARVS CENTROBONTUS (?), AND SE BASTES 

 MARINUS 



BY 



H. CHAS. WILLIAMSON, M.A., D.Sc, F.R.S.E.. 

 Marine Laboratory, Aberdeen. 



{Plates I.-V.) 



Sparus centrodontus, Delaroche. 



This species, Cuvier and Valenciennes* state, was named by 

 Delaroche Sparus centrodontus. According to the French authors, 

 there is doubt as to the identit}'- of the fish named Sparus orphus, L. 

 Dayt gives the name Sparus orphus, Lacep, as a synonym of Sparus 

 centrodontus, Delaroche. Cuvier and Valenciennes proposed to change 

 the name to Pagellus centrodontus. But there is, in my opinion, no 

 necessity for removing this species and Sparus cantharus, L., from the 

 genus Sparus. 



This species is landed at Aberdeen by trawlers during the greater 

 part of the j^ear. In September, 1910, it was being captured in 

 especially large quantities. 



It is known as the Jerusalem Haddock, Bream. Silver Haddie 

 (Loch Fyne). 



A description of this fish is given below. 



Specimens J have been examined during each month of the year for 

 the purpose of studjdng the development of the reproductive organs. 

 In no instance was the ovary ripe. It seems probable that when 

 spawning these fishes may retire to places where thej^ are not taken 

 by the trawl. 



7'he Rrprodiictive Or(jans. 



This species is hermaphrodite. A pair of testes and a pair of 

 ovaries are present in each fish, but the testis and ovary are not 

 always functioning simultaneously. The testis and ovary are 

 intimately combined on each side of the fish. 



* Cuvier et Valenciennes — " Histoire Naturelledes Poissons." T. vi. Paris, 

 1829. 



t Day — "The Fishes of Great Britain and Ireland." 2 vols. London, 

 1880-1884. 



X Mr. Eun.son, tish merchant, Aberdeen, has very kindly given me most of the 

 examples of this and the other species dealt with in this paper. 



(4116) Wt. 403 46— 500— 9/1911. 



