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Part III. — Twenty-fourth Annual Report 



XL— ON TWO CASES OF HERMAPHRODITISM W THE COD 

 (GADUS CALLARIAS). 



By H. Charles Williamson, M.A., D.Sc, Marine Laboratory, 



Aberdeen. 



(Plates XV., XVI.) 



Several cases of Hermaphroditism were noticed among the cod landed 

 in Aberdeen during March, 1906. Two of these were secured from local 

 fish-curing yards for the Marine laboratory. A third was reported to the 

 Fishery Board from Whitehills ; and a fourth is known to have been 

 observed in Aberdeen. 



The specimens here described were examined after having been two 

 months in formaline solution ; they exhibit two different arrangements 

 of the ovaries and testes. In one case, fig. 1, pi. xv. and xvi., a fully 

 developed female reproductive organ bears at the anterior extremity of 

 each ovary a small testis, forming a symmetrical hermaphrodite organ. 

 The other example (fig. 2, pi. xv. and fig. 4, pi. xvi.) shows a single roe 

 of large size united to a full-sized testis. The organ on the right side is 

 female, that on the left is male. 



The symmetrical roe weighed about 5| lb. It contained transparent 

 eggs, showing that the roe was nearly ripe. The testis contained some 

 ripe sperms, but there were none in the vas deferens. The testis, though 

 well developed, was considerably short of being ripe. The main blood- 

 vessel, b.v., of the ova.ry reaches that organ at its anterior extremity. It 

 is continued over the dorsum of the ovary along the base of the mesentery 

 (after giving off a large branch to pass down on the inner surface of the 

 ovary) to unite at the junction of the two ovaries with the corresponding 

 vessel of the opposite organ. Before it reaches the ovary this large 

 vessel gives off two branches b l .v l . and b 2 .v 2 ., one to each end of the 

 loop-formed testis (fig. 2, pi. xvi.). Between the branch blood-vessels and 

 the frill of the testis lies the vas deferens. This duct is closed at one 

 end of the testis loop, viz., at VD, and it opens by its other extremity, 

 V 1 P 1 1 into the ovary, by three small openings. These openings were not 

 so guarded as to prevent the eggs from getting out into the vas deferens, 

 but the eggs found there were small yoked eggs, and they may have been 

 forced out by the handling to which the roe was subjected. A fully ripe 

 egg would probably not pass through the apertures. The general form 

 of the testis is that of a loop ; it is shown diagrammatically in fig. 3. 

 The great development of the testis-fi ill on so short an extent of vas 

 deferens has formed it into a compact mass, wherein the vas deferens is 

 not to be seen until the folds are forced apart. The large blood-vessel of 

 the ovary is accompanied by a thick walled vessel (v.) having a very 

 small lumen. 



The asymmetrical organ weighed 3| lb. The ovary contained trans- 

 parent eggs. Some ripe sperms were present in the testis; but there 

 were none in the vas deferens. In this case a normal ovary is accom- 

 panied by a normal testis (fig. 4). The two unite in the anal region 

 just as two ovaries or two testes do, and their ripe products escape by the 



