AUSTRALIAN MALACOSTRACOUS CRUSTACEA. 205 
cies is very common in its young state, but a great many must 
fall a prey to their many enemies, amongst the chief of which 
may be reckoned Neptunus pelagicus, as large ones are of rare 
occurrence. One that I have procured measures 10 centimetres 
across the carapace, but specimens of this size are seldom found. 
It has a wide distribution: East coast of Australia, New Zealand, 
Japan, and China. 
Tribe CATAMETOPA or GRAPSOIDEA. 
15. Macrophthalmus setosus (M.-Edw.).— This species is 
essentially a burrowing one, frequenting mud-flats. Its burrows. 
may be found here and there among those of Helecius cordiformis 
(q. v.), but cannot be mistaken for the latter on account of the 
acute angle it makes with the surface, whereas the burrows of 
H. cordiformis are vertical and smaller. Colour yellowish brown, 
covered with sete. Port Jackson, New South Wales. Common. 
16. Helecius cordiformis (Dana).—F ound in similar situations 
to the preceding, but is much more common. The mud-flats, 
where these animals dwell, possess a most animated appearance, 
and remind the observer very forcibly of a busy city, of which the 
soldiers are Mycteris longicarpus (q. v.) and the civilians H. cordi- 
formis (of which there are myriads), and all their little legs 
moving in concert make quite a great clatter. They are extremely 
amusing. On anyone approaching they show fight at once, 
holding up their comparatively large ‘‘nippers” as high as they 
can, so that us they retreat—which they do with their “faces to 
the foe ’—they very often roll over backwards, so eager are they 
to show their weapons. The very rotund body is of a deep 
reddish brown colour. New South Wales, Tasmania. 
17. Ocypoda cordimana (Desm.). — The Crabs of this genus 
are noted for their extreme swiftness of foot; indeed, they run so 
fast, and their colour assimilates so well with the sand, that they 
appear like pieces of cotton-wool or feathers being blown along 
‘by the wind. They are found wherever there is a good stretch of 
sandy beach, in which they make their burrows. These burrows 
average about 2 ft. in depth. Hast coast of Australia. 
18. Grapsus variegatus (Latr.). — This is, without doubt, the 
dominant species of Crustacea in Australian waters, is distributed 
‘over a wide area, and presents great variation. ‘They are found 
in great numbers all along the rocks at low tide, but scurry off 
