Page:VCH Cornwall 1.djvu/323

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CRUSTACEANS the ' Long-horned shrimp,' for the proper horn or rostrum Is quite short, scarcely reaching beyond the eyes. Couch says : ' This species has been hitherto unknown as British, but I have examined several specimens taken from the stomachs of fishes from the depths of 1 5 or 20 fathoms. Some of them were of larger size than described from the Mediterranean ; one, not the largest, measuring 3 inches from snout to tail, with antennae of the length of 5 inches.' 1 According to Risso this still rather mysterious animal is semi-transparent, yellowish, with some reddish tints, the second antennae and the longer of the two flagella in the first antennae whitish, the first legs a fine red above, a clear yellow below. Risso himself identifies it with ' Cancer glaber, Olivi, Zool. Adriat. p. 51. PI. V, fig. 4.' Milne-Edwards and O. G. Costa agree that Olivi's species is Pontonia custos (Forskal), and Costa decides that Olivi's variety represented in fig. 5 is quite a different species from that of his fig. 4, but still not Autonomaea. Both Milne-Edwards and O. G. Costa speak of Desmarest as having independently examined the species. That is, I believe, an entire misapprehension. Desmarest adds nothing to Risso, who on his own showing ought to have called his species glabra. Neither does Couch add anything, so that we are left alone with Risso, the inaccurate Risso. To the family Processidae, in which the mandibles are without palp, belongs Processa canali- culata, Leach, often called Nika edulis, Risso. Under the latter name Cocks reports it from ' Stomach of Morrhua aeglefinus, trawl refuse ; rare ' ; and adds, ' Dr. Vigurs procured two living specimens of this rare shrimp, 1 8 September, 1849, Bar Pi nt -' Bate says : 'We have taken it occasionally on stony ground in about 30 fathoms of water.' a With regard to ' Nika Couchii Bell, Stalk-eyed Crust, p. 278,' Bate remarks: 'We have taken this in the same locality as the other. With all due deference to the ability and acute observation of the author of the work cited, I must insist that this is nothing more than a variety of N. Edulis. It was first found by Mr. Couch and sent to Professor Bell, who never saw but this one specimen.' * Bate's opinion is probably correct. The genus Prtcessa is peculiar in having the first pair of legs in general not truly a pair, since one of the couple is chelate and the other simple. The Alpheidae have a mandibular palp. The genus Alpheus exhibits a first pair of legs ill matched in size and shape, but both members chelate. The second pair are also chelate, though on a minute scale. Cocks says of A. ruber, Milne-Edwards, 'The first specimen I found in the stomach of the Gadus morrhua, November, 1845. From that date to the present year, 1849, 1 h* ve procured more than fifty specimens, old and young.' Bell says : ' The only two specimens hitherto found were obtained by Mr. Cocks, of Falmouth, who procured them from the stomachs of cod- fish.' 4 Bate, after referring to Bell, says : ' It has since been taken off the Dodman in thirty fathoms of water. Also in Plymouth Sound. Its more general habitat is on stony ground in about thirty fathoms of water. Its colour salmon, and red at the joints.' 8 In 1868 Bate reported from shelly ground off the Dodman two specimens of Alphtus edwardsii, which, he says, ' we believe to be the first time that this latter species has been recorded as British. We had them alive for several days. Their colour is a brilliant crimson red, A. ruber being rather paler and more banded.' 6 He figures the species, and in 1878 again asserts the capture of A. edwardsii off" the Dodman, but takes no notice of the evidence which the Rev. A. M. Norman had adduced in 1868 that the species figured by Bate was in reality A. megacheles (Hailstone). 7 From this, Norman says, 'A. ruber may at once be distinguished by the four longitudinal carinae of the larger and greatly flattened hand." He further notices that three Cornish specimens of A. ruber in his collection have the right cheliped the larger, and that Cryptophthalmus ruber of Costa is unquestionably a synonym of A. megacheles, not of A. ruber. Bate, in supposing his erroneous record of A, edwardsii to be the first entry of that name in the British fauna, overlooked a paper by J. Couch ' On the discovery of Alpheus Edwardsii on the Coast of Cornwall.' 8 Therein Couch mentions two specimens found in the sponge, Halichondria palmata, hooked up from a depth of thirty fathoms. After dislodgment from the sponge the Crustaceans were plunged in a bowl of sea water. ' The larger of the two was about nine-tenths of an inch in length from the rostrum to the tail, but although of such small size they traversed the vessel with an appar- ently threatening aspect, carrying the larger claw aloft, and especially when irritated, snapping it hard, with such vigour as to be heard over a room of moderate size. The sound resembled, as well in kind as strength, the cracking of a filbert nut, and was reproduced as often as the little creature was irritated.' He describes the colour of the larger example a beautiful reddish orange, dark in the region of the stomach ; of the smaller specimen pale white. But neither did this A. edwardsii stand the test of critical examination by Norman, who showed that it was not an Alpheus but the Typton spongicola of Costa. The Typton spongiosus, described by Bate in 1868, and which as T. spongiosum he upholds in 1878, saying, 'Several specimens of this species were found inhabiting a sponge in 1 Fauna, p. 79. ' ' Revision,' p. 36. * Ibid. 4 Brit, stalk-eyed Crust, p. 271. s ' Revision,' p. 37. 6 Brit. Assoe. Report for 1867, p. 283, and Ann. Nat. Hist. (1868), Ser. 4, vol. ii, p. 119. 7 Ann. Nat. Hist. (Scr. 4), vol. ii, p. 175. 8 Journ. Linn. Soc. Zoology (1861), p. 210. 271