164 A NATURAL HISTORY OF THE SEAS 



continuing the race. It is estimated that only one in a 

 million Cod's eggs ever reach Codhood. 



One of the most prolific of all fishes is the Ling {Molvd) y 

 a single five-foot female weighing 50 lbs., yielding over 

 28 million eggs. 



Care of any sort for the eggs, indeed, seems to be in exact 

 inverse ratio to the number produced. Though whilst 

 the Ling's gigantic brood is turned adrift the Herring's 

 comparatively modest quota of from twenty to forty 

 thousand are in some measure provided for. They are 

 heavier than the surrounding water and sink in clusters 

 until they fall upon shingle, where they become attached 

 by their adhesive covering. This same crude form of 

 attachment is carried to more elaborate lengths by fishes 

 producing small batches of a few hundred or scores only 

 of eggs. In the Sharks and Rays the eggs are often of large 

 size and enclosed in horny capsules, having wiry tendrils 

 or other attachments for anchoring them securely amongst 

 silt or weeds. 



It is interesting to note that in certain viviparous Sharks 

 — amongst the few live-bearing sea fish — the embryos are 

 at first contained in very thin egg capsules which become 

 absorbed prior to birth. 



The egg cases of our native Dogfishes and Rays are 

 familiar to all as " Mermaids' Purses." In the deep-sea 

 Chimeras the egg capsule is shaped like an enormous 

 tent-peg, with the pipe thrust deep into the silt of the 

 sea floor. 



Adhesive eggs are less common with sea fish than with 

 those of fresh-water, in which adhesion is the rule. The 

 eggs of the Lamprey have a bunch of adhesive threads 



