REPORT ON THE AMPHIPODA. 361 



preoccupied. The genus Tiron is " typified " in a new species called Tiron acanthurus, and 

 thus defined : — 



" Forma capitis ex parte cum eadem gen. Oediceri congruit, antenuK superiores vero flageUo 

 appendiculari longo sunt praeditse, et pedes trunci 7:mi paris longitudine pedes anteriores 

 sequanfc, et breves, crassi et unguiferi sunt. Pedes trunci l:mi et 2:di paris graciles, 

 unguo tamen non flexibili instructi. Segmenta caudalia superne in medio longitudinaliter 

 carinata, carina ad marginem posteriorem segrnentorum in aouleum, qui in segmentis 

 4:to et 5:to magnus est, et adhuc in segmento 6:to observatur, excurrente. AntennjB 

 superiores longitudine pedunculo antennarum inferiorum cequales. Prons aliquanto producta, 

 basin antennarum superiorum obtegens, rostro brevi sed acuto. Oculi rubri. Longitudo 

 circ. 10 millim." 



The new genus Oediceropsis is also typified by a new species, which, because the upper antenna 

 are particularly short, is called Oediceropsis hrevicornis, with this definition : — 



" Forma corporis eidem gen. Oediceri valde similis, caput tamen rostro caret, et pedes trunci 

 7:mi paris, qui lougum et rectum unguem habent, et longi et graciles sunt, tamen pedibus 

 anterioribus 6:ti paris non duplo — circ. sesqui — longiores sunt. Antennse superiores non 

 finem articuli penultimi pedunculi antennarum inferiorum assequuntur, et flagello appendiculari 

 carent. Antenuse inferiores magns, fere pediformes, articulo penultimo pedunculi ceteris 

 majore et ad apicem infra setam magnam gerente. Oris partes appendiculares et hujus et 

 anterioris speciei structura solita. Pedes trunci l:miet 2:di paris forma inter se similes 

 manu subcheliformi, ovali, carpo postice aliquantum producto. Pedes trunci 3:tii et 4:ti 

 paris parvi et graciles. Segmentum caudale 7:mum integrum et parvum sed laminare. 

 Pedes caudales ultimi ramis duobus angustis, fere oequalibus. Color flavescens ; oculi 

 rubescentes, sed parura visibiles. Longitudo cir. 8 millim." 



In the subfamily Lysiauassina Lilljeborg gives five genera, which correspond to thirteen out of 

 the seventeen which Boeck has assigned to it. 



Lysianassa, Milne-Edwards, he defines as follows : — 



" Pedes trunci s. fhoracici l:mi paris manu suhcheliformi carentes, ungue non flexibili, segmento 

 6:to sive manu apicem versus attenuate ibidemque hasi unguis vix crassiore. Mandibulx 

 tuberculo molari mininw. Laminx exteriores maxillipedum margine interiore noduloso vel 

 Iseviusculo.'' Within this he distingaishes three species thus :— 



" Lysianassa. 

 Segmentum 



7:mum caudae 



fissum. 



Lamina3 



branchiales . -{ 



' pectinatim plicatse . 1. q}inicornis{ A. Boeck). 



L non plicatas . . 2. Vahli (Krciyer). 

 non fissum, margine posteriore convexo . 3. Costm, M. Edwards." 



Of these the first is Ichnopus spinicornis, Boeck, 1860, the second was called " Soeames Vahli" 

 by Boeck in 1870, the third is the original type species of Lysianassa. 



The second genus, Eiiryienes, has been already described. The third genus, Anonyx, Kroyer, is 

 thus defined : — 



" Pedes trunci {thoraciei) l.mi pans manu subcheliformi armati, ungue flexibili, margine 

 inferiore inamis plus vel minus definito, Mandibulx tuberculo molari mediocri oel magna. 

 Laminee exteriores pedum maxillarium margine interiore plerumque noduloso, raro dentato 

 vel acideato." To this he assigns the following fifteen species, 1. Anonyx ampulla (Phipps); 

 Kroyer, PI. iv. fig. 52, which is rather to be called Anonyx nitr/ax, Phipps ; 2. Anonyx 

 longipes, Sp. Bate, PI. iii. figs. 23-31, called Tryphosa longipes by Boeck, 1870; 

 3. Anonyx gulosus, Kroyer, including his own Anonyx narvegicus, 1851, and the Ayionyx 

 holbolli of Bate and "Westwood; -i. Anonyx nanoides, n. s., PI. iiL fig. 32-34, called 

 (ZOOL. CHALL. EXP.— PART LXVII. — 1887.) • Xxx 46 



