LIFE HISTORIES 349 



spicuous on dissection. The microscope shows, however, that 

 large specimens are invariably female. The characteristic 

 young ova can easily be recognised, but they are embedded in 

 a large amount of fatty tissue, and this fact together with the 

 small size of the ovary, is the reason why the organs were for 

 some time not identified. The ovaries occupy the same position 

 as in other fishes, having the form of a longitudinal band at- 

 tached to the dorsal wall of the body cavity on each side of 

 the intestine. They differ however from the ovaries of the 

 majority of Teleostei in the fact that they do not form closed 

 sacs with the germinal tissue internal ; the germinal tissue in 

 which the ova are developed forms a number of flat folds at- 

 tached transversely to the outer side of the ribbon-shaped ovary, 

 and exposed to the body cavity. There are no ducts, the ova 

 when shed escaping by pores at the side of the anus. 



The male organs are like those of other bony fishes, being 

 somewhat thick, soft, elongated organs, smooth on the external 

 surface, and containing branched microscopic tubes which com- 

 municate with a duct leading to the exterior of the body. The 

 male organs of the eel were first discovered by Syrski at Trieste 

 in 1874, but none in the ripe condition were seen by him. Dr. 

 Jacoby in 1877 at Trieste and Comacchio showed that the males 

 were much smaller than the females. The largest male was 

 not quite 1 ft. 8 in. in length, while the female reached a length 

 of 3 ft. 3 in. 



In the conger also the male is much smaller than the 

 female. The first description of the ripe male conger is that 

 of Dr. Hermes published in 1881. This naturalist was at that 

 time Director of the Berlin Aquarium, and a number of small 

 conger 2 ft. to 2 ft. 4 in. in length were put into the Aquarium 

 in the autumn of 1879. All of these grew rapidly except one 

 which died in June 1880, and was then only 2 ft. Sto in. long. 

 This specimen was found to contain large testes, and microscopic 

 examination showed that the milt which flowed from the organs 

 when they were cut was full of ripe spermatozoa in active 

 motion. 



That this specimen was by no means exceptional in its small 

 size was proved by the researches of the present writer at the 

 Plymouth Laboratory in 1887- 1890. A considerable number of 

 male conger were obtained and kept alive in the Aquarium, and 



