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the left side, of the crab. The parasite referred to would no doubt now stand under some other generic name.

Myra, Leach, 1817, is another genus of common occurrence throughout the Indo-Pacific region, of which the species Myra fugax (Fabricius) has been frequently renamed. It is remarkable for the great length which the slender chelipeds sometimes attain, and which have caused the Japanese to call it the long-handed crab.

Ebalia, Leach, 1817, has an extremely extended range, and includes numerous species, among which several occur in European seas, and four of them in the waters of Great Britain. These four are Ebalia tuberosa (Pennant), Ebalia tumefacta (Montagu), Ebalia Cranchii, Leach, and Ebalia nux, Norman. It is curious that Bell, in his 'History of British Stalk-eyed Crustacea,' should have thought it right to follow Leach in calling the first two of these respectively Ebalia Pennantii and Ebalia Bryerii, while he relegated the earlier names to the synonymy. The resemblance which these little creatures, with their legs all tucked up, assume to a rugged little fragment of stone has been already mentioned. Comparing Ebalia with a genus Phlyxia instituted by Bell in 1855, Mr. Miers says:-The genera Ebalia and Phlyxia are now connected by so many intermediate species, that not one of the distinctive characters mentioned by Bell can be regarded as constant. I propose, therefore, to unite these genera, but to separate the species under two primary sections or sub-genera (for which the names Ebalia and Phlyxia may conveniently be retained) as follows:

'I. Front slightly concave or truncated, not quadridentated (Ebalia).' This is followed by a list of twentysix species.

II. Front with four distinct (usually tuberculiform) lobes or teeth, including the tooth at the interior angle of the orbit (Phlyxia).' This is followed by a list of seven species, in regard to which it is pointed out that all are restricted to Australia. The convenience of having a generic name to indicate so small a mark of separation may well be questioned, but the inconvenience of the sub

K

generic name scarcely admits of question, especially when it leads to the possibility of a creature being called

Ebalia (Phlyxia) undecimspinosa (Kinahan), var. orbicularis,' a name which is even then incomplete without the addition of the names (Haswell) Miers, to show that Mr. Miers has made Haswell's Phlyxia orbicularis a variety of Kinahan's Ebalia undecimspinosa.

Ixa, Leach, 1815, has perhaps, according to Mr. Miers, only one species, though five have been named. This one is the Ixa cylindrus (Fabricius), called Ixa canaliculata by Leach. It is widely distributed in the Indo-Pacific region, and has a very remarkably shaped carapace, transversely rhomboidal or somewhat elliptical, and prolonged at either side into a cylindrical lobe, which is often as long as the width of the main portion of the carapace.

Oreophorus, Rüppell, 1830, the hill-bearer,' and Speleophorus, A. Milne-Edwards, 1866, the cave-bearer,' have names referring to the prominences and depressions in the carapace.

Family 4.-Dorippida.

The afferent channels to the branchia open behind the pterygostomian regions, and in front of the chelipeds. The three terminal joints of the third maxillipeds are not concealed by the fourth joint. The last pair or last two pairs of legs are short and feeble, and raised on the dorsal surface of the carapace. The verges of the male are exserted from the sternal plastron.

The family includes eight or nine genera, the position of Cyclodorippe, A. Milne-Edwards, being rather doubtful, since in it there are no afferent openings to the branchia in front of the chelipeds.

Dorippe, Fabricius, 1798, has a wide range, and includes several species. One of them, Dorippe facchino (Herbst), is found both in the Mediterranean and at Hong Kong. The first two pairs of walking-legs are long, and enable the creature to run fast. The two following pairs are very slender and short. To account for their dorsal position various reasons have been suggested. Herbst

and a third that they help to repel animals that might otherwise tread on the crab's back. The specific name which Herbst gave it means a knave, and is its trivial name

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131

says that the crab can run either way up. Another view is that these hind legs lift foreign objects on to the carapace,

FIG. 10.-Dorippe japonica, von Siebold, a female specimen, with separate figures, showing the chelipeds of the male from the inner and outer sides, the left cheliped being the stouter [de Haan].

among the Italians, in evident allusion to the resemblance it bears to a comic mask. Similarly, Dorippe dorsipes (Linn.) is not inappropriately named by the Japanese “the demon-faced crab.' Dorippe japonica, von Siebold, represented on the preceding page, is closely allied to Herbst's Dorippe facchino.

Ethusa, Roux, 1828, unlike Dorippe, which usually has the carapace broader than long, in general has the carapace much longer than broad. Miers notices that the species of this genus are the forms which evince. the greatest degree of degradation from the Brachyuran type. In other words, they make the nearest approach to the next tribe, which in Mr. Miers' work is not included among the Brachyura. Ethusa mascarone, Roux, is a Mediterranean species. Ethusina, S. I. Smith, 1884, is closely allied to Ethusa, but distinguished by the form of the first antennæ, the basal joints of which are very large and swollen, occupying the whole width of the front,' and crowding back the eyes and second antennæ into an almost transverse position. The type species, Ethusina abyssicòla, Smith, was dredged off the East Coast of the United States at a depth of about 1,500 fathoms, the members of this genus and Ethusa being those which descend to greater depths in the ocean than any of the Brachyura which we have been hitherto discussing. The species Ethusa granulata, Norman, has been transferred to a separate genus, Cymonomus, by Professor A. Milne-Edwards.

Cymopolia, Roux, 1828, has for its type species, Cymopolia Caronii, Roux, from the Mediterranean, but it includes twelve species in all, of which eight have been recently instituted by Professor A. Milne-Edwards from dredgings in the Gulf of Mexico and Straits of Florida. De Haan considered that it ought to stand among the Maiacea, but his opinion has not been followed.

CASHIERING THE ANOMURA

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CHAPTER X

TRIBE V.-ANOMALA

The

THE sternal plastron or breastplate is wide. branchiæ lie obliquely, and may attain the number of fourteen pairs. The vulvæ open not on the breastplate, but in the bases of the third pair of legs.

This tribe of Anomalous Brachyura has long been considered a division of a separate sub-order called the Anomura, meaning Stalk-eyed Crustaceans 'with unsymmetrical tails.' To this division the name Apterūra. was given, to distinguish it from another division called Pterygūra. The first name signifies those that have unwinged tails, the second those that have winged tails. The wings referred to are formed by the appendages of the sixth segment of the pleon, which in the Pterygura are expanded on either side of the telson, but which in the Apterura are not developed. By the transfer of the latter division to the Brachyura its old name becomes unsuitable, since all of that sub-order are apterurous. It contains two legions, the Drominea and Ranininea.

Legion 1.-Drominea.

The carapace is subglobose or subquadrate, the 'front' narrow. The third maxillipeds have the third and fourth joints subquadrangular. The lateral apodemata' of the trunk are united in a common centre, forming a sternal canal. The last pair, and often the last two

1 The apodemata or apodemes are processes formed by an infolding of the cuticle and extending inwards to give surfaces of attachment for the muscles and to assist in protecting the internal organs