374 MRS. E, W. SEXTON ON A [Apr. 28, 



iinguicolare dell a mano cliventa anteriore. (La mano stessa ^ 

 enormemente ingrossata) ; nei piecli mascellari il 1° articolo del 

 palpo e piu lungo del 2° in Ouerina" this article being " piii 

 breve del 2° " in Trischizostoma. 



In answer to Stebbing's words as to the "generic and probably 

 specific identity of the two forms " he says : — " Senza dubbio fra la 

 Ouerina del Golfo di Napoli e il Trischizostoma della coste di 

 Norvegia ognuno a prima vista nota grande rassomiglianza, sopra 

 tutto per la forma generale del corpo, per la grandezza degli occhi 

 e per i gnathopodi anteriori. ISTondimeno, considerando meglio 

 le varie appendici e piu di ogni altra cosa le parti boccali e i piedi 

 toracici del gruppo medio, la differenza dei due Gammarini riesce 

 evidente non solo specificamente, ma anche generieamente." The 

 name Guet^inia, being preoccupied in 1830, Della Yalle changes to 

 Ouerina. Figures are given of the male, the oral parts, gnatho- 

 pods, two perseopods, and the urosome. 



The three specimens described, all males, were taken on 

 " merluzzi" ; two on November 22, 1881, off Cuma in 250 metri ; 

 .and one on December 10, 1881, " al largo d'Ischia " at 150 metri. 

 Length 12-13 mm. 



In 1895, Stebbing (16) in an article contributed to 'Natural 

 Science,' again emphasises the close relationship of the two forms, 

 and considers the characters given by Della Valle too trivial to 

 ■wari-ant the placing them in different genera. 



In 1903, Brian (17) published a note on the capture of a 

 Ouerinia nicceensis in the Gulf of Genoa. The specimen, an ovi- 

 gerous female, 18 mm. in length, was found by Sig. Borgioli 

 in the mouth of a Ghlorophthalmus agassizi. The colour of the 

 living animal he describes as " variants fra il giallo sporco e il 

 rosso mattone." 



Chevreux (18) in 1905 in his ' Liste des Gammarina' taken by 

 the ' Princesse-Alice ' gives : 1. Guerinella nicceensis (Costa), and, 

 in an explanatory footnote, his reason for changing the name ; 

 Ouerinia and Ouerina being so much alike as to lead to confusion, 

 and Guerinella conforming to the rules of nomenclature adopted 

 by the International Congress of Zoology. 



The specimen, an ovigerous female, 19 mm. long, was taken 

 17/7/04 in the " filet a grande ouverture" in the Bay of Biscay, 

 lat. 46° 15' N., long. 7°"09' W., haul from 0-3000 metres. This 

 is the first record of this sjjecies out of the Mediteri-anean. 



In 1906, Stebbing (19) in 'Das Tierreich ' combines the two 

 forms in one species Trischizostoma iiicceense, genus Trischizostoma, 

 family Lysianassidse, taking T. raschii as the female, and Guerina 

 nicceensis as the male ; but in a manuscript as yet unpublished (20) 

 dated 24/7/07, which he has been kind enough to allow me to 

 make use of, he separates them specifically, still retaining, how- 

 ever, the one genus and including in it a third and new species 

 from South Africa. As he has pointed out (16) Boeck's generic 

 name Trischizostoma, 1860, supersedes the Guerinia\d>^^ of Costa, 

 preoccupied in 1830. 



