CRUSTACEANS joint much more expanded distally than is the case in Ampithoe. Bate reports as Cornish four species which he assigns to Podocerus : P. pulchcllus (Leach), P. variegatus, Leach, P. capillatus, Rathke, and P. falcatus (Montagu). But Leach's determinations until recently have been mis- understood. The true P. variegatus of that author was quite a different species from that to which Bate fitted the name. The first and second of Bate's four species should be called Jassa pulchella, Leach. Montagu's falcata remains obscure. Rathke's Podocerus capillatus, distinguished by its strongly setose antennae, has now become Parajassa pelagica (Leach), the two genera Jassa and Parajassa standing in a family Jassidae. On the other hand Podocerus variegatus, Leach, is the type of the true Podoceridae. It is now known to be identical with the species which Bate described under the now discarded name Cyrtophium darwinii. It may be recognized by its protruding eyes and corrugated back, and by the facility with which its appendages break off. 1 Concerning it Bate and Westwood say, ' We have only as yet received specimens of this species from Mr. Webster, some of which he dredged off Falmouth, the others he obtained on the beach, at low water at St. Michael's Mount.' * In the Corophiidae the form which Bate describes as Cerapus atditus, Templeton, from Plymouth Sound, 3 should in my opinion be transferred to the genus Ericthonius (Milne-Edwards). That species of Corophium occur in Cornwall lies under no reasonable doubt, but evidence as to localities and specific distinctions is not very clear. The timber-boring Chelura terebrans, Philippi, of the family Cheluridae, was found by Laughrin at Polperro, and by Norman at Falmouth. 4 The tribe Hyperiidea has hitherto met with scant attention from naturalists in Cornwall. Cocks makes mention of ' Hyperia Latreillii, Edw. Trawl refuse, stomach of Trigla hirundo : rare,' and Bate of Hyperia galba (Montagu), ' taken in the sea floating in medusae, off the coast.' 5 The former name is probably a synonym of the latter. In the Caprellidea the family Caprellidae is beset by numerous difficulties, arising from variability within the species, from differences due to sex and age, and from the many false identifications into which authors have been more or less excusably betrayed. Especially in the genus Caprella (Lamarck), have these circumstances led to confusion. In this genus the first and second pairs of peraeopods are wanting, being represented only by their branchial vesicles. Bate gives to Cornwall an allowance of seven species. 6 But C. linearis (Linn.) probably includes his C. lobata, from Plymouth Sound. Of C. penantis, Leach, Bate using the later name C. acutifrons, Latreille, says, ' Taken in Plymouth Sound ; and Mr. R. Q. Couch informed me that it is not uncommon among corallines in Mount's Bay.' The C, hystrix, KrOyer, which he likewise reports from Plymouth Sound, is regarded by Norman and Dr. Paul Mayer as probably belonging to C, septentrionalis, KrSyer, Mayer distinguish- ing it as ' forma y nodigera.' 7 C. acanthifera, Leach, ' has been taken at Plymouth, on Drake's Island at low water ; as well as dredged in the Sound.' Of ' C. tuberculata, Guerin,' Bate and Westwood say, 'A considerable number were found by Mr. T. L. Couch in the crevices of a crab- pot buoy thrown on the coast at Polperro during a heavy gale in 1854, and Mr. R. Q. Couch obtained the female in Gwavas Lake, and off St. Michael's Mount, among confervae. 8 This state- ment is no doubt due to Spence Bate himself, who is not deterred by that circumstance from mis- quoting it in his ' Revision.' Mayer decides that the British species has nothing to do with Gueiin's C. tuberculata, yet even in his latest work offers no alternative name. 9 I now therefore propose that it should be called C. westivoodi. C. equilibra, Say, is reported by Bate as ' Taken in Plymouth Sound on buoys hid among weeds." Under the now discarded title Proto pedata (Abildgaard), he records Phtisica marina, Slabber, remarking that ' the late Mr. R. Q. Couch took it at Mousehole, Corn- wall.' This genus, though as slender and consumptive-looking as most other Caprellids, has at least the full complement of trunk limbs in seven pairs. Lastly, under the long standing name Protella phasma (Montagu), Bate reports the species which Mayer in 1890 transferred to a new genus Pseudoprotella. In this, as in Protella, the first and second peraeopods are degraded, but whereas they are only one-jointed in Protella, in the newer genus they are two-jointed. The species was found by Mr. R. Q. Couch ' among confervae at Lariggan rocks, Mount's Bay, Cornwall.' Cocks found this and the preceding species, and Caprella linearis, C. acanthifera, and C. penantis, at his favourite collecting station, Gwyllyn-vase. The Entomostraca comprise three extensive divisions, as to which it will be convenient to remember that the Ostracoda have the body enclosed in a bivalved shell-covering and normally un- segmented ; the Branchiopoda have a very variable number of body segments, with or without a 1 Stebbing, in Ann. Nat. Hist, (i 899) Ser. 7, vol. iii, p. 237. * Brit. Sea. Crust, vol. i, p. 482. 8 Ibid. p. 456. 4 Ibid. p. 507.
- Revision, p. 60. 6 Ibid. pp. 61, 62.
7 Die CapreHiden des Golfes von Neapel, Nachtrag (1890), pp. 6 1, 66. 8 Brit. Sets. Crust, vol. ii, p. 70. 9 Die Caprelliden, Nachtrag, p. 61, and Die Caprelliden der Siboga-Expedition (1903) p. 126. 10 Die Caprelliden, Nachtrag, pp. 8, 1 8. I 28l 36
