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much longer, than any of the legs, the first three pairs of which have a tendency to be slender and the last pair of which end in typical swimming-paddles; the antero-lateral borders of the carapace are cut into from 5 (very rarely 4) to 9 distinct teeth. The carapace may be subrotund, but it is usually conspicuously broad."

The sub-family is subdivided into three alliances-Lupoida, Podophthalmoida, and Lupocycloida-the first of which includes, among others, the genera with which we are here concerned.

GEN. CHARYBDIS, de Haan.

1902. Charybdis, Stebbing, South African Crustacea, pt. 2, p. 9. The synonymy has been already given under the reference cited.

CHARYBDIS NATATOR (Herbst).

Plates XXVIII. and XXIX.

1794. Cancer natator, Herbst, Naturg. Krabben u. Krebse, vol. ii., pt. 5, p. 156, pl. 40, fig. 1.

1834. Thalamita natator, Milne-Edwards, Hist. Nat. Crust., vol. i., p. 463, pl. 17, figs. 13, 14.

1835. Portunus (Charybdis) granulatus, de Haan, Crust. Japon., decas secunda, p. 42, pl. 1, fig. 1.

1843. Charybdis granulatus, Krauss, Südafrik. Crust., p. 24. 1899. Charybdis (Goniosoma) natator, Alcock, Journ. Asiat. Soc. Bengal, vol. lxviii., pt. 2, pp. 50, 61.

1907. Charybdis natator, M. J. Rathbun, notes to Stimpson's North Pacific Crust., Smithsonian Misc. Coll., vol. xlix., p. 82.

Under the last reference but one will be found a full synonymy of the species to date, and a description with which the specimen from the Durban Museum seems fully to agree, except in a single particular, probably connected with the exceptional size of the example captured at Durban. Alcock states that the fingers of the chelipeds are about as long as the hand, and says with regard to eleven specimens in the Indian Museum that in the largest specimens the carapace is about 70 mm. long and about 100 mm. broad. Our specimen is 80 mm. long and 113 mm. broad. The hand measured along the lower margin is 133 mm. in length, of which 58 mm. belongs to the thumb, leaving 75 mm. for the palm. On the upper margin the palm is only 60 mm. long, and the movable finger is 63 mm., but in general effect the palm of this specimen might be

regarded as decidedly longer than the fingers. The transverse granulation along the lower surface of the hand is a very notable character.

CHARYBDIS SEXDENTATA (Herbst).

1783. Cancer sexdentatus, Herbst, Naturg. Krabben u. Krebse, vol. i., pts. 2-5, p. 153, pl. 7, fig. 52 (not pl. 8, fig. 53).

1798. Portunus annulatus, Fabricius, Supplem. Ent. Syst., p. 364. 1899. Charybdis (Goniosoma) annulata, Alcock, Journ. Asiat. Soc. Bengal, vol. lxviii., pt. 2, pp. 49, 54.

The synonymy of this species, not unattended by doubts, is supplied with Alcock's usual care in the place above cited. But he does not include Talamita sexdentata, Rüppell, Krabben des Rothen Meeres, p. 4 (Thalamita, p. 28), pl. 1, fig. 1, 1830, nor Portunus (Charybdis) 6-dentatus, de Haan, Crust. Japonica, decas secunda, p. 41, pl. 12, fig. 1, 1835. In his key to the Indian species of Charybdis the present species, in common with C. cruciatus, belongs to a group in which "the antennal flagellum is completely excluded from the orbital hiatus; the ridge that bounds the dorsum of the carapace posteriorly forms a curve with the postero-lateral borders; no spine on posterior border of arm." Furthermore, these two and some other species have "no distinct transverse ridges on the carapace behind the level of the last spine of the antero-lateral borders," not more than three large spines on the anterior border of the arm; the orbits have no decided dorsal inclination and their major diameter is never more than one-third the width of the interorbital space. But whereas in C. cruciatus the first spine of the antero-lateral border is anteriorly truncated and notched, in the present species it is acute, and here the sixth pleon segment of the male has the sides parallel, not, as in the other species, convergent.

From other species with which this is perplexingly surrounded it appears to be sundered by the comparative sharpness of the frontal teeth, the comparative smallness of the last antero-lateral tooth, the character of the last peræopods, which have the merus or fourth joint nearly twice as long as broad and the hind margin of the propodite or sixth joint serrated in a large part of its extent. The sixth pleon segment is not quite so long as broad. According to Alcock "the major diameter of the orbit is only a fourth the width of the interorbital space." This appears to suit our specimens, but I am not quite clear as to how the measurements are taken.

The male specimen from the Durban Museum has a carapace

In the female the carapace is Another female, with carapace middle frontal teeth blunt, more Herbst's Cancer fasciatus, on his

45 mm. long by 63 mm. broad. 40 mm. long by 55 mm. broad. 41 mm. by 48 mm., has the two advanced than their neighbours. pl. 49, fig. 5, might well have been drawn from such a specimen as this.

Alcock ends his account of the species by saying: "But for high contrary authority, I should consider this species to be identical with the Cancer sexdentatus of Herbst's pl. 7, fig. 52." He gives Cancer fasciatus, Herbst, vol. iii., pt. 1, p. 62, pl. 49, fig. 5 (1799) as a very doubtful synonym, subsequently referring it by preference to Charybdis (Goniosoma) merguiensis, de Man. Those who wish further to understand the difficulties of identification should study Dr. de Man's chapter on "Goniosoma merguiense, n. sp.," in the J. Linn. Soc. London, Zool., vol. xxii., p. 82, 1888.

Since the above account was written, Stimpson's report on North Pacific Crustacea has appeared. At p. 81 it records from Hong Kong Charybdis sexdentata (Herbst) de Haan, with references to the sexdentatus or sexdentata of Herbst, Rüppell, and de Haan. Miss M. J. Rathbun, the editor, gives in a footnote as the correct name of the species Charybdis japonica (A. Milne-Edwards), without further explanation. In part 2, p. 10, of the present series I have already explained that Henri Milne-Edwards, in his Hist. Nat. Crust., vol. i., p. 463, 1834, under his Thalamita annulata (Fabricius), has erroneously quoted Cancer sexdentatus, Forsk., as a synonym of Portunus annulatus, Fabricius, although Forskäl did not name any Cancer sexdentatus, Herbst's species of that name being the true predecessor of Charybdis annulata (Fabricius).

GEN. LUPA, Leach.

1813. Lupa, Leach, Edinb. Encycl., vol. vii., p. 390.

1897. Portunus, M. J. Rathbun, Proc. Biol. Soc. Washington, vol. xi., pp. 155, 160.

1902. Lupa, Stebbing, S.A. Crust., pt. 2, p. 11.

1907. Portunus, M. J. Rathbun, notes to Stimpson's North Pacific Crust., Smithsonian Misc. Coll., vol. xlix., p. 76.

I feel bound to reiterate my protest against my friend's use of the name Portunus, based on Latreille's supposed restriction of that genus in 1810, when he mentioned P. pelagicus as a typical species of it. Lamarck in 1801, Syst. Anim. sans Vert., p. 151, mentions by name only P. depurator, Fab., which, on Miss Rathbun's principle, may therefore claim to be the typical species, although no doubt

Lamarck gives references to others. But Latreille himself in 1802, Hist. Nat. Crust. et Ins., vol. iii., p. 23, defines Portunus, with "Exemple. Portunus depurator, Fab.," and without mention of any other species. Judging by his later writings, I cannot suppose that either in 1802 or 1810 he had any intention to restrict the genus when naming an "exemple" or "type." But if he did it accidentally, surely the accident happened in 1802, and made P. depurator the typical species. In his Cours d'Entomologie, pp. 349, 350, in 1831 Latreille's references to Portunus puber and Lupa pelagica make it clear that he was himself unaware of having done anything to make the latter species a Portunus in preference to the former.

LUPA PELAGICA (Linn.).

1758. Cancer pelagicus, Linn., Syst. Nat., ed. 10, p. 626. 1798. Portunus pelagicus, Fabricius, Suppl. Ent. Syst., p. 367. 1813. Lupa pelagica, Leach, Edinb. Encycl., vol. vii., p. 390. 1899. Neptunus pelagicus, Alcock, Journ. Asiat. Soc. Bengal, vol. lxviii., pt. 2, p. 34.

1907. Portunus pelagicus, M. J. Rathbun, notes to Stimpson's North Pacific Crust., Smithsonian Misc. Coll., vol. xlix., p. 76.

A dry specimen of this well-known species from the Durban Museum measured 150 mm. in extreme breadth of the carapace.

CATOMETOPA.

FAMILY GRAPSIDE.

1900. Grapsida, Alcock, Journ. Asiat. Soc. Bengal, vol. lxix., pt. 2, pp. 283, 389.

GEN. GRAPSUS, Lamarck.

1801. Grapsus, Lamarck, Syst. Anim. sans vertèbres, p. 150. 1900. Grapsus, Alcock, Journ. Asiat. Soc. Bengal, vol. Ixix., pt. 2,

pp. 389, 390.

"Four antennæ,

The eyes at

Lamarck's original definition of the genus is: short, articulated, concealed beneath the carapace. the angles of the carapace, with short peduncles. Body depressed, almost square, carapace transverse, deflexed in front. unguiculate the anterior pair chelate." He bases it upon Cancer grapsus, Linn., for which he substitutes the new designation Grapsus

Ten feet,

pictus. He gives after the Linnean name references to Petiver, Catesby, and Herbst, and adds to the synonymy "Cancer tenuicrustatus, Herbst, Cancr. 2, p. 113, t. 33, 34, with a reference to Seba. He includes as a second species in the genus "Grapsus depressus, n., Herbst, t. 3, f. 35, a. b.," since referred to Plagusia. In his key to the Indian genera of Grapsidæ, Alcock distinguishes Grapsus and Geograpsus as having the front less than half the greatest breadth of the carapace, while it is more than half that breadth in Metopograpsus and Pachygrapsus. In the definition of Grapsus, however, he speaks of the front as about half the breadth of the anterior border of the carapace." In a dried specimen of G. strigosus from the Durban Museum the front is somewhat more than half the greatest breadth of the carapace.

GRAPSUS STRIGOSUS (Herbst).

1799. Cancer strigosus, Herbst, Naturg. Krabben u. Krebse, vol. iii. pt. 1, p. 55, pl. 47, fig. 7.

1802. Grapsus strigosus, Bosc, Hist. Nat. Crust., vol. i., p. 203. 1838. Goniopsis strigosa, McLeay, Illustrations Zool. South Africa p. 66.

1838. Goniopsis flavipes, McLeay, loc. cit., p. 66.

1843. Goniopsis strigosa, Krauss, Südafrik. Crust., p. 46.

1900. Grapsus strigosus, Alcock, Journ. Asiat. Soc. Bengal, vol. lxix., pt. 2, p. 393.

1907. Grapsus strigosus, Stimpson, North Pacific Crust., Smithsonian. Misc. Coll., vol. xlix., p. 118.

The dried specimen already referred to has a carapace 28 mm. long and 30 mm. broad. The largest of 76 specimens observed by Alcock measured 59 mm. in length by 63 mm. in breadth.

Concerning G. flavipes, McLeay, Krauss says that it is only distinguished by blood-red bands, and otherwise entirely agrees with the description of G. strigosus, in company with which it is. found.

The Durban Museum specimen agrees in the colouring of the walking legs with Herbst's figure. In the chelipeds the tooth at the inner angle of the wrist is straight, in accordance with Alcock's description.

Miss Rathbun, in notes to Stimpson (loc. cit., p. 119), makes Stimpson's Grapsus longipes a synonym of G. strigosus, to which Stimpson himself admitted that it was closely allied.

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