SAfiS ON REPRODUCTION OF THE COD. 215 



of four inches in length and ;iboiit seven months old, as cst minted, art the bottom, at a depth of 

 several fathoms. 



In 18G8 he began his observations in Noveinber, and in November and December found young 

 fish six or seven inches in length at a depth of eight to twelve fathoms, usually in the vicinity of 

 steep ledges aud rocks. This year he remained until March, and in February found great num- 

 bers of young Codfish, the average length of which was about one foot, at an average of twenty 

 to thirty fathoms, on sandy bottom. "In the beginning," he remarks, "I thought that these must 

 be two-year-old fish, but when I afterwards set my line in shallower places I also collected smaller 

 fish, so that I soon had all the different grades of size." 



This last visit extended over into the year 1869, aud at the time of his departure the schools 

 of spawning fish were again on the ground. He had thus traced the development of the Codfish 

 throughout a period of twelve months, and had secured a very complete chain of evidence with 

 which to bind together the isolated facts regarding the growth and habits of the young fish which 

 had hitherto been or should hereafter be observed. 



From 1870 to 1873 he continued his observations upon the young and adult fish, and in 

 midsummer found Cod at a distance of twenty to thirty Norwegian miles from the shore, and 

 at a depth of from one hundred to one hundred and fifty fathoms. These observations, as 

 has already beeu remarked, are of the utmost importance, and the reports of Professor Sars are 

 full of observations of the most suggestive kind concerning the food, the movements, and the 

 general habits of the fish. 



The other paper referred to, which is of equal value, is the report of Mr. E. E. Earll upon the 

 natural history and artificial propagation of the Cod, as observed at the station of the United 

 States Fish Commission at Gloucester, Massachusetts. 1 His remarks upon the reproduction of the 

 Codfish are here quoted in full, with the single observation that no one has so carefully observed 

 the spawning habits of any other species offish. 



"The Cod is one of the most prolific of the ocean fishes, and we find not only thousands but 

 millions of eggs in a single female. All members of this family contain large numbers of eggs, 

 but the Codfish is the most prolific of all. 



"The exact number of eggs in a female varies greatly with the individual, being dependent 

 largely upon its size and age. To ascertain the number for the different sizes, a series of six fish, 

 representing various stages of growth from twenty-one to seventy-five pounds, was taken, and 

 the. eggs were estimated. Care was exercised that the series should contain only immature 

 females, so that no egg should have been lost, and that all might be of nearly equal size. 

 The ovaries were taken from the fish and their weight accurately ascertained; after which small 

 quantities were taken from different parts of each and weighed on delicately adjusted scales, 

 the eggs in these portions being carefully counted. The number contained in a given weight 

 being known, it was easy to ascertain approximately the entire number for each fish. 



"The results obtained are given in a table, quoted below, showing a twenty-one-pound fish to 

 have 2,700,000, and a seventy-five-pound one, 0,100,000. The largest number of eggs found in the 

 pollock was 4,029,200, and in the haddock 1,840,000. 



"When the eggs are first seen in the fish they are so small as to be hardly distinguishable, 

 but they continue to increase in size until maturity, and, after impregnation, have a diameter, 

 depending upon the size of the parent, varying from one-nineteenth to one-seventeenth of an inch. 

 A five to eight pound fish has eggs of the smaller size, while a twenty-five-pound one has them 

 between an eighteenth and a seventeenth. 



1 Report of United States Commission of Fish and Fisheries, pt. 6, 1878, pp. 685-740. 



