On the Reproduction of Deep-sea Fishes. 173 
Genus Bicoromyia, nov. 
Generic characters.—Calcar on hind tibia very short and 
weak, situated near apex; third wing-vein setulose at base 
above and below, curved forward at apex; prosternum, 
pteropleura, hypopleura, yentral surface of scutellum, and 
basal abdominal sternite bare ; both intra-alars and the 
prealar strong. In other respects as Phavnia. 
Genotype, Spilogaster trispila, Bigot. 
One male and one female from Monte Video, Uruguay, 
and one female from La Plata City, Argentina. 
XVI.—The Reproduction of Deep-sea Fishes. 
By J. D. F. Gitcurist, M.A., D.Sc. 
[Plate I] 
Very little is known as to the nature of the eggs and spawning- 
habits of deep-sea fish. This is no doubt due to the fact that 
these fish are seldom procured in quantity, and, in deep-sea 
expeditions, attention has naturally been directed mainly 
to securing and preserving new forms of marine animals. 
The various structural adaptations of deep-sea fish to the 
peculiar conditions under which they live have therefore 
received a good deal of attention, while little or nothing is 
known of their reproduction—whether, for instance, they 
have pelagic or demersal eggs or are viviparous. The single 
exception to this, so far as I am aware, is the case of the 
Macrurus celorhynchus, the ovarian eggs of which were 
described by Costa in 1865. Somewhat similar eggs were 
found by Raffaele (1888) in the sea at some depth, and he 
suggested, though with some hesitation, that these might be 
the eggs of Macrurus. Raffaele’s eggs are apparently iden- 
tical with those found by Hensen a year earlier and by 
subsequent observers at later dates. 
The Cape seas present certain facilities for the procuring 
of deep-sea fish at certain localities, where, in a few hours’ 
steaming, a depth of 1000 fathoms can be reached. During 
a former marine survey and its present continuation a certain 
amount of information has been procured, which may be of 
interest, as it appears to throw some light on the eggs and 
spawning of deep-sea fish generally. 
Maerurus fasciatus is very abundant on the west coast in 
