Cagle (1940:229 and 232) has graphically described and illustrated the hatching of the five-lined skink, and numerous observations in the present study have served to corroborate his description. The first indication that the time of hatching is at hand is a twitching or jerking movement within the egg which continues until the shell is slit. According to Noble and Mason (1933:5) the shell is slit with the elongate premaxillary egg tooth which has its distal third bent forward nearly at right angles to its base. Some young remain for an hour or more with only the snout visible, however, once the head is extruded it is not again withdrawn unless the lizard is badly startled. The eyes are opened and blinked slowly, closed for a few minutes, and opened again. After the eyes have become adjusted, the fore-body emerges and the front legs are freed. In one clutch, observed by Cagle, hatching time for individual eggs varied from 45 minutes to five and three-fourths hours. If startled by visual or tactile stimuli, the little skink may lunge forward through the slit shell, with a sudden straightening of its body, and rush away for several inches. Its movements are slow, stiff and clumsy as compared with those of a skink that is a few days old and fully active. Hatching of a clutch ordinarily extends over 24 hours or more. Some of the young may be fully hatched and active before others from the same clutch have slit their eggshells.
Eggs ready to hatch ordinarily weigh somewhat more than one gram, up to at least as much as 1.7 grams, but much of this weight is made up of water absorbed during incubation. The hatchlings usually weigh from .2 to .45 grams. For each of two eggshells recently vacated, that were washed and squeezed dry, weights were approximately .125 grams. Hatchlings of the same brood differ perceptibly in size with several per cent variation in total length, and weight. Some seem to be less fully developed than others. On July 8, 1952, hatching of the last young in a clutch was observed. Upon emergence, it differed in appearance from the others of the brood hatched a few hours earlier. The top of its head bulged slightly as in fetuses. The umbilicus was not yet closed, and the protruding yolk mass hindered the hatchling’s movements and made crawling difficult. In order to progress it had to stand high off the ground to prevent its ventral surface from dragging. Protrusion of the yolk mass has been described in newly emerged hatchlings for the closely related E. anthracinus (Clausen, 1938:3-7) as well as in fasciatus. Cagle (loc. cit.) states that the mass of yolk is at first about 3 mm. in diameter, but is completely used at the end of the third day. A group of young retained by him, without food, died the sixth day after hatching, seemingly from starvation. Three of five recently hatched young were found by Cagle to have eaten ant pupae placed in a box with them on the preceding day, even though the skinks still retained the yolk masses. One hatchling of this group ate its own tail that had been broken off in handling. Cagle described a color change taking place during the first few hours after hatching; the ground color, dull greenish at first, darkens to an iridescent black, the pale stripes are altered from an original tan color to bronze, with a tinge of reddish on the head, and the ventral surface which is partially transparent showing the outlines of the internal organs at first, soon becomes opaque white.
Contrary to the statement by Noble and Mason (1933:5) that in captivity the hatchlings seldom stayed together more than a few hours, litters of young fully active, a day or two after hatching were found in the nests with the females still looped around them on several occasions. On one such occasion, although the brood scattered immediately into surrounding vegetation where they hid, I succeeded in catching the female and six of the young, and put them all together in a nylon bag to carry them back to the laboratory. Several hours after the bag had been placed on a table it was noticed that the family had again gathered into a compact cluster in the bag with the female’s body looped around the young in the characteristic brooding position seen in those with young or eggs in their nest cavities. When hatching is complete, the female may leave before the young have dispersed. On August 5, 1950, a nest under observation was found to have all of the young or most of them still clustered in the cavity, but the female was not in evidence. The young were active, and immediately took alarm as the rock was raised exposing them. Almost instantly, they scattered and vanished. Subsequent search revealed five of the young, each poorly concealed in tufts of grass or under dry leaves or other ground litter at the edges of the depression where the rock had lain. Once hidden, these young were reluctant to run again and depended on concealment.
Having once left the nest, the young probably do not return to it, as many nests examined within a few days after hatching were never found occupied either by females or young after their original dispersal. As soon as the dispersal occurs family ties are permanently severed. On July 19, 1950, a group of active hatchlings was observed moving about over a log, on what was probably the first day of activity away from the nest. The log was in the bottom of a steep-walled gully, where it had come to rest the night before. It had been an erect but dead and partly undermined snag on the edge of the gully, and was blown down that night in a violent thunderstorm. Most of the log was held clear of the rushing water in the bottom of the gully by projecting limbs. The little skinks were darting in and out of holes and crevices in the log, pausing frequently to bask. As many as four were in sight simultaneously, but probably the total included several more, as it was difficult to keep track of individuals. An adult female, presumably the mother of the litter was also present, but she took no interest in the young, and they showed no evidence of dependence on her. On the contrary, several times when one or another of the young happened to come near the female in the course of its wandering, and noticed her, it was seen to shy away in sudden alarm.
Fig. 11. Sizes on specific dates of young hatched in 1950 and 1952. Approximate size ranges at different times of year, and differences in trend between the two years are brought out.
The young were much more active than the female. These and other young observed in the open were almost constantly in motion. Pauses to bask at any one spot were of only a few seconds duration. A certain log in Skink Woods evidently was the site of one or more successful skink nests each year that observations were made, although a nest was actually found in it only in 1948. On July 26, 1950, recently hatched young were active on this log. Temperature was about 22°C. and the young were alternating frequently between shade and sunshine to maintain their body temperature. Collectively they seemed to cover every square inch of the log surface, poking and probing into niches, crevices and insect borings. They had a tendency to seek out the highest points on the log as resting places.
In moving about, foraging or sunning, the young often carry the tail arched high, and keep it in motion with slow squirming undulations. These undulations may be continued even when the lizard itself has come to rest momentarily. The movements of the tail together with its vivid blue color serve to attract attention to it. Such behavior has not been observed in adults or partly grown young. Jopson (1938:90) observed an instance in which two dogs cornered a young five-lined skink (either the present species or E. laticeps) but were distracted by the wriggling of its bright blue tail “either dropped by autotomy or knocked off” so that the skink itself was allowed to escape. On another occasion these same two dogs attacking an adult male skink, were not distracted by the wriggling but dull colored broken tail, and they killed the lizard.