"captured on this date (1st June) were in turn establishing their outlyer burrows, which providing they the parents survive. would in turn become parent burrows with their outlyer breeding burrows. at some period while the actual parent burrow was still in use (not charted), & the charted burrow was still comparatively small but enlarging the long 12 ft. direct connecting burrow as made, this later became merely a convenient place for storing the loose sand dug out in enlarging the charted burrow. Just how long a burrow takes to reach the size of the one charted is difficult to state with any degree of accuracy but from observations I do not think it would be less than 2 years + possibly not more than 3 years. This would seem to point to a long fast rate of breeding. It Generally speaking any burrows with about 40 ft. of more or less direct tunnels can be classed as an established parent burrow, few are more than 40 to 45 ft. & none over 50 ft. have more lately numbered brood. The short single style is a first brood burrow. (Actually I do not know if the species breeds more than once a year so the term broods year is very loosely applied.) I feel sure they would expect to find the species breeding like rabbits. N. B. A light shower of rain fell during the early part of the night 31st May-1st June which wiped out all tracks in the sand (only a matter of a few points fell, the first rain actually to fall here since late last year, roughly 5 months) & clearing the day a close check up on tracks was made. Mammals are not as plentiful as was at first thought to be the case from the tracks in the sand. In this desert country tracks remain plainly visible & apparently fresh for long periods & it is the accumulation of tracks which make it appear as if animal life was abundant: At the present time rats (collected) appear to be very abundant about the flats near the waterhole but scarce out on the sandhills, they were evidently very plentiful before the flood as thousands of drowned carcasses may be seen about the country. What appears to be another species of rat or small bandicoot is present but rare in the sandhills (not seen or collected). Kangaroo Rats (collected) are abundant on the sandy flats above water mark & about the bases of the sandhills & on flats between sand hills but seem to be rare on the sandhills themselves. Mice (collected) are not common anywhere except in certain restricted areas close about their warrens & these warrens are generally pretty far apart. Fat tailed mice (collected) are not set very common but seem to be evenly but thinly distributed over the whole area but to a less degree on the sandhills, but more so on the flats at the immediate foot of the sandhills thinnning out slightly further out across the flats, but they appear to be nowhere plentiful. They seem to be definitely wanderers having no fixed warrens or burrows but seldom do dig feeding burrows live & thrive about patches of onion grass, possibly slightly enlarging such a burrow for breeding, remaining to rear a brood & then move on. They do not appear to be breeding at present but to be roving the country. Rabbits are fairly numerous about the waterhole. Foxes are very plentiful about the waterhole & adjacent sand hills. Dingo's are very numerous about the water hole & far out into the sand hills seem to be still fairly plentiful. No other mammals or tracks have been seen.