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Appendices to Fifth Annual Report 



many embryos were found to have hatched out, and were lively. Twenty- 

 four hours later (22nd July) the embryos on the nests in the dish, and 

 which had, therefore, not been in water for 144 hours, were still living. 

 Some were found to have hatched out, and were wriggling on the damp — 

 now nearly dry weed, mixed up with the nests. Other embryos on 

 being put in salt water immediately commenced to jerk violently, and very 

 soon broke their way out. These young wrasses in the salt water gra- 

 dually died off about the time when the yelk was nearly exhausted. 

 Many lived after hatching for four or five days, and a few lived for fully 

 six days, at which time the caudal portion of the notochord was still quite 

 straight, and there was yet no sign of pelvic fins. In the water these little 

 larval wrasses of about 3| mm. in length when hatched, were very active, 

 continually wriggling up to the surface of the water, with a quick jerky 

 movement of the tail and a rapid vibratory movement of the pectoral fins, 

 to sink slowly again for several inches, when the upward movement was 

 repeated. When the glass jar in which they were kept was placed opposite 

 a window they all, without exception, crowded to the bright side, mostly 

 keeping near or close to the water's surface. The procedure described was 

 repeated daily with the same results until July 26, when the weed and nests 

 were found to be nearly dry, warm, and slightly decomposing ; the remain- 

 ing ova in the nests being now dead. They had, therefore, lived without 

 water in this merely damp state for nearly ten days. 



The place in which the nests were found was about half-tide mark, so 

 that they must in the natural state have been about six hours at a time 

 uncovered by water, and that repeated twice every twenty-four hours. 

 Half their embryonic existence then is passed out of the water, but even 

 knowing this it is surprising to find that they could survive such a length 

 of time as that recorded above. If the parent fish, as would seem probable, 

 take some considerable time to construct these nests, or if they visit the 

 nests after the ova have been deposited, it is interesting to note that from 

 the position of the nests in this instance they would have to retire from 

 them during the above periods of time, and for a distance of at least 30 

 yards (at low water) twice every twenty-four hours. 



In the egg when received the embryo was curled up with its 

 head doubled over the yelk-sac and the tip of the tail reaching, and 

 before hatching overlapping, the anterior end. The pectoral fins ap- 

 peared as folds, without evidence of rays. The eyes were large ; the 

 ears simply showed a pair of small circles within them. After hatch- 

 ing, however, the semicircular canals could readily be made out. The 

 general appearance of the embryo when hatched will be better under- 

 stood from the sketch (Plate XL) than from description. Before hatching 

 there were visible a few primitive rays about the tip of the tail, and these 

 increased anteriorly, although not over the whole length of the fins, 

 while the embryos were kept alive after hatching. In the free embryo 

 the pectoral fins were relatively long, and each appeared as a strong anterior 

 thickening, supporting behind the delicate fin, in which primitive rays like 

 those of the median fins appeared. At hatching the jaws were slightly 

 open, and the lower one could be moved slightly. The embryos, which 

 were examined while on the semi-dry weed, were always found to be quies- 

 cent, and the action of the heart was very slow, if not entirely inactive. 

 When placed in water the action of the heart invariably commenced. The 

 larval fish on hatching were pigmented in single spots of black and dull 

 yellow. The pigmentation extended along almost exactly two-thirds of the 

 total length of the body from tip to tip, the posterior third having no spots, 

 and the black spots were sparsely scattered over the yelk-sac, but in general 

 were of a rather smaller size in that region than those on the body. There 



