Mermaids’ Purses Hold Young Fishes.

Star (Christchurch), Issue 19238, 27 November 1930, Page 8

Mermaids’ Purses Hold Young Fishes.

Nature Notes

By

James Drummond, F.L.S., F.Z.S.

YI7HEN PEOPLE were more fanciful and * * credulous than they are now, they believed that the horny egg-cases of some sharks and rays were mermaids’ purses. Many fishes lay eggs by the thousand. Sharks seldom produce more than twenty or thirty at a time. Some species of sharks produce their young alive. Most of them make the egg-cases formerly believed to be mermaids’ purses. Dog-fishes are small sharks, and it is stated that a young dogfish has been seen clearly in all stages of development through the transparent walls

The egg-cases illustrated here belong to a ray, a member of a species, Raja nasuta, found occasionally off the New Zealand coasts. One side of this egg-case was convex, the other concave. On the horns, there were tubes, which opened on to the exterior and through which the young ray breathed while it was in the egg-case. Mermaids’ purses found in fairly large numbers on New Brighton beach are eggcases of the elephant-fish, which belongs to the group of the sharks and rays. In the centre of one of these mermaids’ purses there may be seen a cavity that contained an embryo elephant-fish. In each of these egg-cases a passage, closed by a valve, leads from the cavity to the exteriefr. Through this passage the young elephantfish escapes from its prison.