Copepoda taken in the West of Ireland. 139 



branch quite rudimentaiy. Cletodes, however, has the first 

 pah- of antennge six-jointed, the second antennae without a 

 supplementary branch, and the four pairs of swimming-feet 

 all alike, the inner branch ending in two long filaments. 

 Under these circumstances we propose to call Claus's genua 

 Lilljehorgia \>j the new name Orthopsyllus. 



Genus PoRCELLiDiUM, Glaus. 



1. Porcellidium Jimhriatum^ Glaus. 



?Sterope ovalis, Goodsir, Ann. & Mag. Nat. Hist. vol. xvi. (1845), pi. xi. 

 fig. 11. 



Dredged on a bottom of decaying vegetable mud in Bir- 

 tirbuy Bay, and on Laminarice in Clifden and Ventry 

 Bays. 



It seems to us most probable that Goodsir' s figures and 

 description {he. cit.) apply to this species, and not to Zaus 

 ovalis as supposed by I)r. Glaus. If this could be ascertained 

 with certainty, Goodsir's nomenclature would have to be adopted 

 on the ground of priority. 



2. Porcellidiuni viride (Philippi). 



Thy (me viridis, Phil. Arcliiv fiir Natm-g. 1840, p. 190, Taf. iv. fig. 2. 

 Porcellidium denfatum, Glaus, Die frei-lebend. Copepod. (1863) p. 140, 



Taf. xxii. figs. 2-5 ; and Beitriige zur Kenutniss der Entom. (I860), 



Taf. ii. figs. 19-22. 



Dredged in Birtirbuy Bay in company with the preceding 

 species ; on weeds in Clifden, Westport, and Ventry Bays. 



There can be little doubt that Dr. Philippi's figure applies 

 to this species ; and we therefore adopt his specific name ; 

 but the generic term Thyone is preoccupied, having been 

 applied by Oken to a genus of Holothuriadee. 



3. Porcellidium suhrotundum^ Norman. 

 P. suhrotundum, Noiiuan, Last Shetland Dredging Report, p. 297. 



Dredged in Birtirbuy Bay with the foregoing ; also on the 

 fronds of Laminarice in Clifden Bay. 



4. Porcellidium tenuicauda, Glaus. 



/'. tenuicauda, Glaus, Beiti-age zur Kenntniss der Entom. (1860), p. 6, 

 pi. ii. figs. 10-15 ; and Die frei-lebend. Gopepod. p. 140. 



A few specimens taken from the interior of the " bulb " of 

 Laminaria Irdhosa in Birtirbuy Bay ; also on weeds in Clifden 

 and Ventry Bays. Scarce. 



