190 Transactions. — Zoology. 



Basal joint of antennules hardly visible from above. 



Outer maxillipedes with all the joints smooth on the outer 

 margins. 



' Chelipedes large, granular ; meros with a strong obtuse 

 tooth on its upper margin ; carpos with the outer and upper 

 margin thin and nearly entire or with a slightly defined tooth 

 at the proximal end, lovv-er margin with about three shallow 

 teeth near the apex or quite entire ; propodos wide, with 

 strong curved fingers. 



Ambulatory legs compressed, with the meros smooth and 

 much dilated, especially in the two last pairs ; propodos with 

 numerous longish hairs, that of the anterior pair spinose on 

 the lower margin; dactylos short and very hairy. 



Colour : Slaty-blue above, lighter below. T, W. Kirk, 

 describing living examples (Trans. N.Z. Inst., vol. xi., p. 396), 

 says, " Above dark-blue, greenish-blue, or sometimes even 

 black ; below green, getting much darker towards the pos- 

 terior margin of the anterior legs ; anterior face of wrist a 

 bright red; mobile finger and antennee deep brown." 



Size : Length of carapace, 17 mm. ; breadth of carapace, 

 16 mm. ; length of antennae, 27 mm. When the chelipedes 

 are stretched as widely as they will go naturally the apices of 

 the carpi are distant 49 mm. from one another, while the 

 tips of the fingers are 90 mm. This is taken from the largest 

 specimen in my collection. 



Distribution. — Australia and Tasmania. 



Habitat. — This is one of the commonest of the New 

 Zealand shore-crabs, and always occurs close to and a little 

 below high-water mark. It lives under stones, its flattened 

 carapace and greatly compressed claws enabling it to lie very 

 close to the ground in such localities. It is an active animal, 

 with powerful weapons of defence in its chelipedes, with 

 which it can give a sharp nip. 



2. Petrolisthes novse-zelandise, Filhol. Plate XXI., fig. 9. 



1885. Petrolisthes novcB-zelandice, Miss, de I'ile Campbell, 



p. 108, pi. xlviii., figs. 1 and 5. 

 1885. Petrolisthes stewarti, Filhol, I.e., p. 410, pi. xlviii., 



fig. 1. 



Carapace somewhat coarsely granular, with a short spine 

 (not always well defined) on each side at the level of the 

 anterior part of the cardiac region, and an acute spine outside 

 the eyes ; a transverse depression crosses the carapace be- 

 tween the eye-sockets, and is defined posteriorly by a row of 

 hairs ; the front is slightly depressed, and is elevated into 

 two rounded lobes on the inside of the eye-sockets, with a 

 groove between them, the whole front being more or less 

 armed with sharp teeth. 



