THE TARDIGRADA OF THE SCOTTISH LOCHS. 681 
There is some doubt as to the precise nature of the apparent perforations of the 
dorsal plates of certain species. 1 suspect that they may arise by decay of the granules, 
and for this reason have made no use of them as specific characters. They are found 
| in living animals, but are commoner in empty skins. That they are of some specific 
value is shown by their constant occurrence in association with definite arrangements of 
plates and spines. Where they occur, the perforations are very distinct, and marked 
by clean sharp edges. 
Legs.—The first leg has often a small sharp spine, the last leg a similar spine, or 
more commonly a blunt palp, near the base. Both of these have probably been 
generally overlooked, and may yet be found to be always present. The last leg has, in 
most species, a serrate fold of skin about the middle of its length, which I call the fringe. 
The claws are four in number in most species, probably in all, when fully grown and 
mature. Generally the inner claws of each four have a decurved spine, called the barb, 
near the base, or as high as half-way up the claw. The outer claws are devoid of barbs, 
except in a very few species (Z. blumi, etc.). The barbs of the outer claws are straight, 
and point outwards or upwards. The barbs of the last legs are larger than the others, 
and often these alone have them; there may be as many as three barbs on each outer 
claw of the last legs. 
Teeth and Pharynx.—tThe teeth are always very long and straight, enlarged and 
forked at the ends, which are often closely applied to the pharynx ; the points enter the 
mouth. The pharynx is sometimes minute and round, sometimes pretty large and some- 
what cordate. As a rule there are no rods, such as are found in Macrobiotus, two 
obscure curved lines which diverge from the end of the gullet probably representing 
them ; but RicuTers has seen rods in EL. wslandicus. I have never seen symplex forms 
in this genus. 
Reproduction.—All lay the eggs in the moulted skin. It has been thought that 
the number of eggs is characteristic, as it is in many species of Macrobiotus. To a 
Rertain extent this is so; but two species have been observed to lay eges when still very 
“small (Z. mutabilis and FE. reticulatus), laying then only one egg, while larger 
examples laid two, three, and four respectively. 
| Development.—Comparatively few of the species have been seen to hatch out, all 
which have been so observed having only two claws, which leads RicHrERs to suppose 
hat all hatch in this form. Against this must be placed the fact that some individuals, 
of species which lay large eges, have been found, so small that they might easily be 
_ supposed to be newly-hatched larvee, but with four claws and all the outward characters 
of the adult. These species were abundant in the collections where they occurred, and 
“increased in them, yet two-clawed larvee were never found (e.g. EL. reticulatus). 
The larvee usually lack some of the setee possessed by the adult, and those which 
they have are relatively shorter. J] don’t know that any example has ever been kept 
under observation from its hatching to maturity ; but where a species is abundant, 
examples may be selected at all stages of growth. In examples which I have seen 
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