CRUSTACEANS 



first added to our list by Borlase, since he calls it Squilla lata. The character which Sowerby 

 mentions, that in this form the hindmost legs are chelate, applies only to the female sex. 



PaKnurus vu/garis, Latreille, is as common as Arctus ursus is rare. It has had various local 

 names. Borlase calls it the ' Long oyster,' Leach the ' Thorny lobster,' Jonathan Couch the ' Craw 

 fish ' or ' Red crab.' Its frequent occurrence in Cornish waters is vouched for by J. Couch and Cocks, 

 and R. Q. Couch when discussing the metamorphoses of the Crustacea says : ' The fishermen also 

 abundantly supplied me with gravid specimens of this species.' 1 He was thereby enabled to describe 

 and figure the first stage of this crustacean. At a later date both he and his father discussed the 

 Phyllosoma-stage of Pa/inurus. 2 But their work has now chiefly historical interest. 3 



In the Astacidea the family Nephropsidae is represented here by the Common Lobster, Astacus 

 gammarus (Linn.) to which Borlase had applied an even more appropriate name in the very year, 1758, 

 which is now accepted as the starting point for priority in zoological nomenclature. Under his section 

 XII, ' Of Shell-fish,' he is evidently comparing the common ' craw-fish ' and the common lobster 

 when he writes : ' Besides the muscle, limpet, cockle, wrinkle, and crabs of all kinds, for better 

 nourishment we have the long-oyster (the Locusta marina Aldrovand. de Crustat. chap. 2 tab. 2), and 

 the lobster, or Astacus verus, much superior in delicacy of food to the former, and in such plenty on 

 the coasts of Cornwall, that well-boats come to load, and carry them alive to London and elsewhere.' 4 

 He adds a tantalizing footnote, that, ' in the spring and summer season the largest are bought for 

 fourpence each, sometimes less, in Mount's Bay.' To the scanty notes on Crustacea thus far 

 extracted from his pages a lively addition can here be made. After explaining the wonderful force 

 with which an oyster is able to close its valves and keep them shut, he continues, ' and (as I have 

 been informed by a clergyman of great veracity, who had the statement from a creditable eye-witness 

 to the fact) its enemies have a skill imparted to them to counteract this great force. As he was 

 fishing one day a fisherman observed a lobster to attempt an oyster several times, but as soon as the 

 lobster approached, the oyster shut his shell ; at length the lobster, having waited with great attention 

 till the oyster opened again, made a shift to throw a stone between the gaping shells, sprung upon its 

 prey and devoured it.' 5 How much of its charm would natural history lose without the assistance 

 of veracious clergymen, creditable eye-witnesses, and fishermen the last above all being noted for a 

 sort of exquisite accuracy in relating the incidents of sport ! Yet one cannot help remarking that 

 precisely the same story was told many hundreds of years ago concerning very different actors. In 

 the first edition it is not a clumsy-fingered lobster that so adroitly pitches a pebble between the valves 

 of a gaping oyster, but the ingenious little Pinnotheres that plays this trick upon the comparatively 

 gigantic Pinna. In the modern aquarium curators should by all means provide sightseers with 

 opportunities for witnessing these displays of strategic sagacity, nor must it be forgotten that the 

 nimble stomach of the starfish has well-attested success in oyster-opening. 6 Under the various names 

 of Homarus vulgaris, H. gammarus, and H. marinus, Couch, Cocks, and Bate speak of the lobster as 

 frequenting Cornish waters. Adam White and G. B. Sowerby correctly name it Astacus gammarus. 

 Bate is probably right in saying that it would be ' desirable as much as possible to discourage the 

 destruction of lobsters while bearing spawn : the loss of one lobster in berry is the destruction of 

 some 60,000 to 100,000 young animals of the same kind.' 7 It should, however, be remembered 

 that the mother and brood which man has spared may be swallowed at one gulp by a conger, and 

 that in any case an average of two mature survivors out of the swarm which each prolific pair is 

 capable of producing will suffice to keep the number of parental lobsters from diminution. In 1880 

 Bate instituted a new species under the name Nephropsis cornubiensts, 6 but this he subsequently recog- 

 nized as a young form of the common lobster. 9 



The freshwater crayfish, Patamobius pallipes (Lereboullet), belonging to the family Potamobiidae, 

 has not hitherto been recorded from Cornwall. Borlase says : ' In our Cornish rivers we have not the 

 jack, perch, carp, crayfish, or others with which Providence has stocked the rivers in the more inland 

 parts of Britain, as it were to make amends for their being so distant from the much greater variety 

 of sea-fish.' 10 Although the crayfish and crawfish are undoubtedly named by alternative spellings of 

 the same word, Borlase, as we see, groups the former with true fishes and the latter with molluscs or 

 shell fishes. The freshwater crayfish and the saltwater crawfish are not far apart in their organiza- 

 tion, but Borlase thought of the latter as the ' long oyster ' and classified it accordingly. R. Q. Couch 

 in 1843 ^y 8 tnat > when beginning his researches into the transformations undergone by young 



1 Cormv. Soc. (1843), p. 37. 



* See Brit. Assoc. Rep. for 1857 and Journ. Linn. Soc. for 1858. 



3 See J. T. Cunningham, ' On the development of Palinurus vulgaris, the Rock-Lobster or Sea Crayfish, 

 in Journ. Mar. Biol. Assoc. (1891-92), vol. ii (New Ser.), p. 141. 



* Nat. Hist. Cormv. p. 274. * Op. cit. p. 275. 

 6 Jcurn. Mar. Biol. Assoc. (189597), vol. iv (New Ser.), p. 266. 



' ' Revision,' p. 34. 8 Brit. Assoc. Rep. for 1880, p. 160. 



' Challenger Macrura (1888) Reports, vol. xxiv, p. 177. I0 Nat. Hist. Cornw. p. 262. 



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