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Note on a Conger with Abnormal Gonad. 



By 

 A. E. Hefford, B.Sc. 



With one Figure in the Text. 



Among a sample of seven small Conger, from 58 to 77 cm. in length, 

 obtained from the Plymouth Fish Quay on 31st March, one was found 

 with unsymmetrical reproductive organs. The other six were im- 

 mature females with the normal pair of ovaries. The abnormal 

 specimen has a right gonad quite similar to the ovaries of females at 

 the same stage of maturity. It is bandlike in form, extending along 

 the whole length of the abdominal cavity. The inner or left side is 

 covered with smooth peritoneal epithelium (mesoarium). The greater 

 part of the surface of the right (outer) side is raised into transverse 

 lamellae containing the as yet little-developed ova embedded in fat- 

 tissue. For about one to two millimetres from its free edge, the organ 

 consists of a strip of fat-tissue quite free from germinal cells, and there 

 is a similarly constituted longitudinal fold — here and there divided 

 into a subsidiary one — extending parallel to and about 2 mm. from 

 the free edge and bordering the lamellated germinal area. The ovary 

 is 17*5 cm. long, its greatest width 12 mm., and the widest part 

 of the lamellated area is about 7 mm. 



The left gonad is a sterile ovary, the transverse germinal ridges 

 being quite absent. Along the line of attachment there is a narrow 

 longitudinal ridge of fat-tissue, fairly well developed anteriorly, but 

 becoming discontinuous towards the hinder end ; then a narrow strip 

 of bare peritoneal epithelium (the area which is normally covered with 

 the egg-bearing lamellae); and along the free edge are folds of fat- 

 tissue similar to those occurring in the normal ovary. 



I am indebted to Mr. J. T. Cunningham for his kindness in examin- 

 ing an,d giving his opinion upon this specimen. 



It is interesting to note that this abnormal individual was the 

 sixteenth Conger examined by me since March 14th with the object of 



