Also the so-called "white-bait" is not a distinct species, but consists chiefly of the fry or the young of herrings and sprats, and is obtained "in perfection" at localities where these small fishes find an abundance of food, as in the estuary of the Thames.
Sprats are very often confounded with young herrings, which they much resemble, but can always be distinguished by the following characters: they do not possess any teeth on the palate (vomer), like herrings; their gill-covers are smooth, without the radiating striae which are found in the shad and the pilchard; the anal fin consists of .from seventeen to twenty rays, and the lateral line of forty-seven or forty-eight scales.
Large quantities of sprats are caught.
The harbour yields sprats which are in great repute.
It is now known to consist of the young fry of herrings and sprats in varying proportions mixed with a few shrimps, gobies, sticklebacks, pope-fishes and young flounders: but these impurities are as far as possible picked out from the whitebait before it is marketed.
The fishing is carried on from February to August, and samples taken in the successive months were found to contain the following percentages of herrings, the remainder being young sprats: 7, 5, 1 4, 3 0, 8 7, 75, 52.
Hence it will be seen that sprats predominated in February, March, April and May, herrings in June and July.
The fisheries are important - for herring, mackerel, sprats, cod, salmon, lobsters and anchovies.
In the following December large numbers were taken together with sprats at Torquay.
The so-called "Norwegian anchovies" imported into England in little wooden kegs are nothing but sprats pickled in brine with bay-leaves and whole pepper.