The male is much like the female, but more slim, and the milt just like that of other fish. I can only conjecture that fecundation is accomplished through the medium of the sea-water, admitted by the curiously-contrived floodgate of the female, carrying in the milt-germs, and washing them over the ova.
The actual period of utero-gestation I am by no means sure about, but I am inclined to think they breed twice in the year. It is worthy of remark that the young mature fish are very large, when compared with the size of the mother. In a female fish eleven inches in length, the young were three inches long—the adult fish four-and-a-half inches high, the young an inch.
The only instance I can find recorded of a viviparous fish bearing any analogy to the _Embiotocidæ_ is the viviparous blenny (_Zoarces viviparus_, Cuv.). Of course I exclude the sharks and rays. Of the viviparous blenny little or nothing appears to me to be known. On reference to Pennant’s ‘British Zoology,’ all he says is, that it was discovered by Schonevelde, and that Sir Robert Sibbald afterwards found it on the Scotch coast, and it was mentioned by Linnæus in his account of the Swedish Museum.
I quote the following paragraph verbatim from Pennant’s ‘British Zoology.’ Speaking of the blenny, he goes on to say: ‘It is viviparous, _bringing forth two or three hundred young at a time_. Its season of parturition is a little after the depth of winter; before midsummer it quits the bays and shores, and retires into the deep, where it is commonly taken. It comes into the mouth of the River Esk at Whitby, Yorkshire, where it is frequently taken from off the bridge.’
In Cuvier’s ‘Animal Kingdom’ (vol. i. ‘Fish’), all I can glean is that the blenny is viviparous. Yarrel, in his ‘British Fishes,’ speaks of a Mr. Low, who put a number of the small fishes (the young of the blenny) in a tumbler of sea-water, in which they increased in size, but eventually died from the want of fresh-water. Again, he quotes a Mr. Neil, who saw in the Edinburgh market, in 1807, several dozens of young fish escape alive from the female. ‘The arrangement of the perfectly-formed young in the fœtal sac of the gravid female is very remarkable.’