36 Papers from the Department of Marine Biology. 



24 by 27. The largest fertile eggs measured 18 by 18 by 19, 19 by 19 

 by 20, 19 by 19 by 22, 20 by 20 by 21. Incidentally these measure- 

 ments show that the eggs are rarely round, some are markedly ellip- 

 ticalone 22 by 22 by 26 mm. 



To ascertain the average size, the following data are selected out of 

 the large amount available. Of live eggs 138 were measured as follows : 

 Longest diameter only: 17.5 mm., two eggs; 18, nine; 18.5, eleven; 

 19, thirty-nine; 19.5, ten; 20, thirty-eight; 20.5, eight; 21, nineteen; 

 21.5, twenty-two. Average of 138 live eggs 18.8 mm. Of preserved 

 eggs, 189 were measured as above: 16.5 mm., three eggs; 17, one; 

 17.5, one; 18, four; 18.5, two; 19, thirty-four; 19.5, eleven; 20, 

 sixty-four; 20.5, ten; 21, forty-nine; 21.5, five; 22, five. Average 

 of 189 dead eggs, 20 mm. The average of the 327 eggs is 19.5 mm. 

 From the above it will be seen that the largest number of eggs meas- 

 ure 19, 20, and 21 mm. in longest diameter, the 20-mm. eggs being the 

 most abundant 102 6ut of 327. Normal eggs of this size are shown 

 in figure 8, plate in, while the egg of figure 9, plate iv, is about the 

 same size but has an older embryo. 



In connection with the foregoing data, the following measurements 

 should be given, since they are of the smallest eggs, taken as a lot, 

 which have been found in the six years' search. They measured in 

 longest diameter: 15 mm., one; 16, three; 16.5, one; 17, four; 17.5, 

 one; 18, ten; 18.5, one; 19, seven. The average for the 28 eggs is 

 17.7 mm. This average, however, would be much lower if the last 

 three lots of eggs of normal size were omitted, or even the one 

 last lot only. These eggs were taken on July 21, 1910, and contained 

 embryos having black stippling on the dorsal surface. At the same 

 time there were obtained, from another fish, 5 larvae which seemed to 

 be from 2 to 3 weeks older than these embryos. All these things lead 

 to the conjecture that possibly these smaller eggs are a lot coming to 

 maturity later and are of a second laying. On these points see page 31. 



Not only is there great variation in the size of the eggs, but also in 

 the number carried. Twice I have taken fish with only 2 eggs in the 

 mouth. The smallest incubators caught during this research were 

 13 and 15.5 inches over all. Each carried 4 eggs. Other small numbers 

 of eggs incubated were 2, 5, 8, 11 (in 2 fish), 13, 14, 15 (in 2 fish), 

 16, etc. The largest number found was 55 in a 22-inch male. Notable 

 also are 50 (22-inch fish), 45 (taken twice), 38 (22- and 20-inch 

 fish), 36 (from a notably small fish 17.25 inches long), 35 (22-inch), 

 32 (fish, 20.25 inches long), and numerous catches in the twenties. 

 Once a large male was found with only one egg in his mouth (the 

 only instance anong hundreds captured), but from the great size of 

 the buccal cavity it is probable that other eggs had been thrown out. 



That these large numbers of colossal eggs do not, however, entirely 

 fill the capacious buccal cavities of these fish may be readily perceived 

 by referring to the calculations given on pages 34 and 35. 



