250 THE VOYAGE OF H.M.S. CHALLENGER. 



from wliich it is here distinguished was named CaUisoina punctata by O. G. Costa ia 

 1840, but not described till 1851 (see preceding Note). It must be considered the type of 

 the genus, as Spence Bate suggests, Brit. Mus. Catal., p. 84, note, though he had not been 

 able to find tlie description of it. Costa's species Gammarits montanus from Lago del 

 Matese, and Gammarus longicaudatus from the drinking water of Naples, are given here 

 for the first time. They are not mentioned in the B. M. Catalogue, from which Amphiilwr. 

 inxquipes and Amphitlwe gracilis are also omitted. All these four are described at length 

 in Costa's E. s. Crost. Amf. d. E. d. Napoli. 

 The genus Am^Mthonotus, A. Costa, is thus explained : — " Illis ex Amphithois speciebus 

 constitutum est hoc genus, quse dorsum vel omnino carinatum et spinosum, vel saltern 

 nuibusdam abdominis articulis si non et thoracis postice in spinam vel dentem productis 

 habent ; ex quo peculiarem habitum prEebent. Amph. marionis, Edw. ; panopla, Kroyer ; 

 carinatus, ejusd. et quae sequuntur ad hunc genus pertinent." The type species, Am^JhitJionotus 

 acanilwphthahvus, A Costa, which is here said to be " affinii< Amph. marionis," was after- 

 wards, under the name Amphithonotus marioids, by Costa himself made a synonym of 

 " Amphithoe marionis, Edw.," and must, as Boeck says, be included along with tliat 

 .•species in the synonymy of Dexaminc spinosa. The next species, given as Acanthonolus 

 (juttatus, A. Costa, and said to be very near to Ampliifhoff carinata, is evidently meant for 

 Amphitlwnotus guttatus, as given in the addendum above mentioned. Costa in his 

 subsequent work does not notice this, but silently transfers the species to his genus 

 Nnfofro2ns, which Spence Bate and Boeck agree in referring to the genus AtyJus, Leach, 

 and also agree in misspelling Notrotopis, though Costa gives the derivation voItos, back, 

 and TpoTTts, keel. The species guttatus is omitted from the B. M. Catalogue. Since both 

 the species, acanthophthaJraiis and guttatus, belonged to genera already established, the genus 

 AmpMfhanotus, created to receive them, must be considered to have perished at its birth. 

 The genus jEpimeria, A. Costa, is thus defined : — " Hoc genus, Amphithois et Amphithonotis 

 maxime affine, epimeris quarti et quinti articuli thoracis elatis, caeteris valde majoribus, 

 simul clypeum sjepius inferne emarginatum formantibus, dignoscendum. Dorsum fere ut in 

 Amphithonotis." 

 Of this genus, Spence Bate remarks that it apparently " differs in nothing from Acanthonotus of 

 Owen, of which probably it is a synonym." Boeck does not accept this view, but he 

 identifies both the type species, Epimeria tricristata, A. Costa, and Acanthonotus mrenii, 

 Bate and Westwood, with Gammarus corniger, Fabricius, 1779, under the name Epimeria 

 rornigera. Tlie Brit. ISIus. Catal., in rendering the above generic definition, says, " Coxie 

 of the first and second pairs of pereiopoda long, the rest considerably broader," but Costa's 

 meaning is that the coxaj or side-plates of the second and third pairs of perseopods are 

 prominent, very much larger tlian the rest. 

 In Hope's Catalogue it may be observed that he inserts Grid ornithoramphus, Cocco, as well as 

 Ornithoramphus eocmi, N'atale, although de Natale clearly explains that his species is the 

 same as Cocco's. As to the genus Carcinococcus and the species assigned to it, de Natale, 

 1850, says, "Finalmeute il mio Carcinococcus andra tra gli Stomapodi Unicorazzati, 

 Erictini — Dedicandone la specie al mio Maestro il Prof. Costa di Napoli — ho voluto 

 foggiarue il nome suo Carcinococcus ; da quello dell' illustro Prof. Cocco, ad imitazione di 

 Carlo Luciano Bonaparte che sopra uno Scopelino scoperto dal Ch. Ittiologo di Messina 

 foggi6 il suo Ichthiococcus — di cui le specie Ovatus,.e Poicerix sono proprie del nostro 

 pnrto." Hence these three species are here quite out of place. Leucothoe parthejiupai a 

 Costa subsequently withdrew. His later Coropldum aclierusicum and Vihilia speciosa 

 probably answer to Awlouinia aclierusica and Elasmocerus speciosus. There are several 

 other genera and species named, of which I can give no account. Some of them are per- 

 haps described in de Natale's letter to Achille Costa, of which I extremely regret that I have 

 never been able to obtain or see a copy. (See Appendix.) 



