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Show 34 ZOOLOGY OF TilE VOYAGE OF TilE BEAGLE. appearance of the tympanum, the paucity of palatine teeth, and the total absence of an interdigital membrane on the hinder feet. These characters being either merely comparative or unimportant, were not considered by Bibron as sufficient to warrant a generic separation, and I have followed him in retaining the species amongst the Cystignat!ti. It was first discovered by Messrs. Quoy and Gaimard at King George's Sound, in Australia, where it was also obtained by Mr. Darwin. It is a beautiful species ; the back being of a rich brown colour, with a pale orange fascia extending along the sides from the eye to the thigh, becoming bright orange on the flanks. Thighs nnd legs banded with rich deep brown and bright orange. GENus-BORBOROC<ETES. Bell. Lingua ovata, postice libem, rotu,ndata; antice subacuminata. Dentes palatini in fasciculis binis plUs miniisve obliquis, pone nares posteriores positi. Tympanum celatum. Digiti anteriores ltaud palmati; posteriores ad basin tantum cute connexi. Glandulre cutanere nullm. Sacculi vocales (maris) ut'rinque sub lingua nascentes. The two species on which I have founded this genus approach so nearly to some species of Cystignatltus, that it is not without hesitation that I determine on considering them as typical of a new generic form. The principal characters on which I have founded the distinction are the position of the palatine teeth, the form of the tongue, the concealment of the tympanum, the absence of glands and pores on the skin, and the connexion of the base of the hinder toes by a rudimentary palmar membrane. It is true that some of the species of Cystignatltus, as that genus is at present constituted, agree with the present form in some or other of these particulars ; but upon the whole they are sufficiently distinct; and in fact the genus Cystignatltus, as left by M. Bibron, appears to me to stand in need of revision and dismemberment. The species constituting the genus now proposed, are however both new. The genus Borbo1·ocmtes will probably stand, in its natural affinities, between Cystignatltus and Cyclorampltus, from the latter of • which it differs in the situation of the palatine teeth, in the degree to which the hinder feet are webbed, and the comparative length of the hinder legs. The two latter characters are of importance as indicating a difference of habit; and we find that Cyclorampltus has proportionally short hinder limbs, with the toes |