A STRANGE CLAW 189 
seven ego's, which, as so commonly in deep-water species, 
were extremely large. From one of these Mr. Spence 
Bate extracted a young animal, and this proved to be not 
unlike the young of the lobster at the same stage, but 
more advanced, thus so far confirming the view that the 
great size of the deep-water ova is in relation to the 
more than usual advancement of the embryo before it is 
hatched. 
Family 4.—Thaumastochelide. 
The carapace is produced to a flattened point or ros- 
trum. ‘The first pair of antennze have on each peduncle 
two long subequal flagella; the second have a scale or 
exopod. ‘The first pair of trunk-limbs are chelate, un- 
equal, somewhat unsymmetrical; the small second pair 
are chelate, subequal, symmetrical; the outer branch of 
the uropods is larger than the inner. The branchiz are 
filamentous, cylindrical. 
To this family Spence Bate assigns only two genera, 
one of which is British. 
Thaumastochéles, Wood-Mason, 1874, is appropriately 
named ‘the creature of wonderful claws.’ The type spe- 
cies, Thaumastocheles zaleucus (von Willemoes Suhm) (see 
Plate X.), was taken by the Challenger from a depth of 450 
fathoms in the West Indies, along with a great number of 
other curious marine animals frequenting the globigerina 
ooze in that locality. It is blind, and not only without eyes 
but without eye-stalks, unless perchance the latter are re- 
presented by a pair of tubercles projecting from the ‘front.’ 
The ‘ front ’ is sub-membranous and translucent, and Spence 
Bate supposes that the optic nerve may terminate so 
closely behind it as to receive impressions of light. But 
though there are no eye-stalks, there are excavations 
in the anterior margin of the carapace corresponding to 
orbits, and also depressions in the first pair of antennz 
such as eye-stalks often rest in. The inference then is 
clear that eye-stalks once existent have been lost, and this 
probably from their being detrimental instead of useful to 
a burrowing creature. The burrowing character is in- 
