Reprodadive Organs of Sparas Gentrodontus. 



23 



•■ The ripe fishes are supposed to have been got to the south of Aberdeen. 



fSex not known. J Also a fish 47em., recently spent ; sex unnoted. 



§The data given in this column do not include the condition i!i every 



one of the fishes. 



In this species, as Kroyer* showed, the larvae develop in the ovary ; 

 internal fertilization is therefore necessary. 



The adult fish is known by its having ripening reproductive 

 organs, or by its being spent. Males measuring from 35 to 47 cm. in 

 length were adult. Females measuring from 17 '4 to 24, 26-5, 31 to 

 50, 74 cm., were adult. It is often easy to recognise a spent ovary 

 from the fact that larvae may have been retained in it, and these, 

 although they have become shrivelled, betray their presence by the 

 black pigment of the e3'es. A second character which is also of value 

 in the ovary is the presence of the old follicles, which can be recog- 

 nised for some time after the ovarj?' is spent. 



The adult fishes may be sexually distinguished, previous to 

 dissection, by the fact that in the male there is a large urogenital 

 papilla (penis), {pa., Fig. 62), while in the female this papilla is flattened 

 out into an apron-like fringe (w. fr., Fig. 73). The urethra opens on 

 the apex of the papilla, and on the distal border of the fringe {arth., 



*Collett, R,— "Norwegian North Atlantic Expedition, 1876-1878." Vol. III. 

 Zoology ; Fishes. Christiana, 1880. 



