35 
similar, but the cardiac region in dorynchus possesses a rounded 
elevation on which are three very small tubercles in a triangle with 
the base forward (*.*). In /eptochirus the cardiac region is occupied 
by three spines, but here the afex of the triangle is forward (.*.). In 
addition, /eptochirus is more substantially built, and grows to a much 
larger size. By a comparison of the specimens you will observe that 
in dorynchus the joints of the chele are swollen and rotund; in 
leptochirus they are more nearly cylindrical, and longer. The ‘‘ hand ” 
or terminal joint of the chelz in doryuchus is not equal to two-thirds 
of the length of the carapace, whilst in /effochirus it is slightly in 
excess of the entire length of the carapace. But there is another 
very important mark whereby the male /effochirus may be known at 
a glance. On the thorax beneath there is a raised tubercle of 
polished white, which is peculiar to /eptochirus, though a differently 
shaped tubercle of similar character marks the Mediterranean species, 
L. thoracicus. 
L. dorynchus in my experience delights to cover its upper surface 
entirely with a slimy yellowish sponge. Nature has only clothed the 
mountains and valleys of its carapace with a scrubby coating of 
minute bristles, and I presume it plants a cutting or two of the 
sponge in the valleys whence they spread until the whole surface is 
covered with a homogeneous layer. I have not seen this planting 
done, but the specimens I have obtained have all been coated evenly 
in this fashion, and have had to be scraped. ‘The covering is applied 
to the upper surface of the chelee as well as the carapace. ‘There is 
a great advantage in covering oneself in this fashion ; it is akin to the 
wisdom of the leaf-rolling larvae, which gain by one effort a disguise 
and a series of meals. About three weeks since an individual came 
into my possession, and I placed it in an aquarium where it had for 
companions an Lchinus miliaris and a fine Galathea strigosa in a 
beautiful scarlet coat diversified with lines of dazzling blue. The 
walls were well draped with green confervee, whilst dozyachus, lesser 
limbs were decked out with small fronds of deep crimson weeds, and 
before he had been there many hours he appeared to feel acutely that 
he was not in harmony with his environment. It is true there was a 
rough piece of serpentine in the centre of the vessel, in which crimson 
tints predominated, and he made the most of this by clinging tightly 
to it, head downwards ; but all the time he evidently realised that his 
yellowish sponge had closer affinity with the green tapestry. Anyway 
he commenced to strip off his crimson rags, and next morning he had 
not one on. Some he had eaten, the others were lying on the floor 
of the vessel. Then he followed the example of the “chznus, and 
tried to cover himself with patches of the green confervee, but evi- 
dently there was not sufficient body in it to serve his purpose, for he 
gave up that attempt. He clung to his sponge covering, however, 
or rather he allowed it to cling to him; but after he had been thus 
situated for a fortnight he began to feel hungry, and then the full 
beauty of his arrangement came out. Reaching across his carapace 
