352 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [142] 



to three inches long and filled with numerous eggs, the number varying 

 from 20, or less, up to about 200. The transparent eggs are arranged, 

 in the well-formed capsules, in six or more rows, and are so closely 

 crowded that they touch each other and often take polygonal forms, 

 especially when preserved. 



How many of these capsules are deposited by one female is very un- 

 certain. Probably several females are concerned in the formation of 

 the larger clusters. The eggs are mostly laid in June and July, but 

 many are laid in August, and some even in September. By the 11th of 

 June, in the vicinity of New Haven, inany of these eggs contain em- 

 bryos in advanced stages of development (Plate XXX, figs. 1, 2). The 

 embryos, before hatching, can swim around inside the eggs. 



These embryos are very beautiful objects to observe under the micro- 

 scope. 



Even at this early period some of the chromatophores are already 

 developed in the mantle and arms, and during life, if examined under 

 the microscope, these orange and purple vesicles can be seen to contract 

 and expand rapidly and change colors, as in the adidt, but the phenomena 

 can be far more clearly seen in these embryos owing to the greater trans- 

 parency of the skin. In the young the chromatophores are very regu- 

 larly and symmetrically arranged on the arms, head, and mantle. At 

 this stage of development the eyes are brown. In these embryos a 

 remnant of the yolk-sac (y) appears to protrude from the mouth, but it 

 is really connected with the space around the mouth and pharynx, and 

 into this it is eventually absorbed. 



The more advanced of the embryos were capable of swimming about, 

 when removed from the eggs, by means of the jets of water from the 

 siphon (s), which is developed at an earlier stage. The arms {a'-a"") 

 are then short, blunt, very unequal, with few minute suckers; the dorsal 

 arms are very small, while those of the 2d and 3d pairs are successively 

 longer, and have distinct suckers ; the tentacular arms {a'") are longer 

 and larger than any of the others, and have larger suckers, which 

 already, in some examples, can be seen to form four rows, but in this 

 stage the peduncular part of these arms is short; the ventral arms {a"") 

 are about as long as the 2d pair, and bear several suckers. The mantle 

 (m) is short, and the caudal fins (/) are very small, short, lateral, and 

 separately attached to each side of the blunt posterior end of the body, 

 thus recalling their adult condition in Rossia. The eyes (e) are large 

 and prominent; the rudimentary beak (d) and odontophore (I) are dis- 

 tinctly visible. The two otoliths (o) are very distinctly visible, as 

 highly refracting ovate bodies, above the basal part of the siphon, one 

 on each side. The ink-sac (i), attached to the rectum (t), is conspicuous 

 on account of its dark color; the gills (g) are provided with a small 

 number of transverse processes; the heart (h) and the branchial auricles 

 (W W) are easily seen while they continue to pulsate. The pen exists 

 only in a rudimentary condition, as a thin cartilage. 



During July and August the young (figs. 3-5), from less than a quarter 



