DUBLIN NATURAL HISTOEY. 161 



Before concluding, it may be interesting to compare the relative dis- 

 tribution of the genera and species in the east and west, when we arrive 

 at the following results, excluding from our comparison those strange 

 forms, Bodotria, Alauna, &c. 



Beachyuea. 



Common to both districts, 23 



Unrecorded in east, made up as follows : — Achaeus, 

 Pisa, Maia, Xantho (3 ?), Portunus (2), Ebalia (?), 



Thia. Those genera peculiarly typical italicized, . 10 



Unrecorded in west, 



Brachyuri, — 33 

 Anomouea. 



Common to both, 11 



Unrecorded in east, viz., Pagurus (1), Munida (?), . 2 



Unrecorded in west, viz., Pagurus (1), Galathea (1), 2 



Anomoura, — 15 

 Maceottea. 



Common to both, .11 



Unrecorded in east, viz., Crangon (2), Alphceus, 



JSfika, Athanas, Palsemon (1), Hippolyte (1), . . 7 

 Unrecorded in west, viz., Hippolyte (1), Crangon (2), 



Palsemon, 4 



Macroura, — 22 



Stomapoda, common to both, ........ 2 



Omitted in above list, 8 



— 10 



Total Crustacea podophthalmia, 80 



The Irish species unnoticed in these lists are — 



Inachus leptocheirus. 



Belfast (0. C), Clifden (W. T.) 



Xantho tuberculata, Polybius Henslowii, Pinnotheres pinnae. — Ob- 

 tained once in the south. 



Gebia deltura, Callianassa subterranea, Calocaris Mac Ancfo-ece. — Ob- 

 tained once in the north. 



Pasiphcea sivado. — A single specimen in Dublin Bay. 



Careful research will, doubtless, disturb these conclusions slightly ; 

 and I am sure that many unrecorded species, especially among the 

 Anomoura and Macroura, yet remain to reward the labourer in these 

 prolific fields of watery research. 



In conclusion, with regard to the provisional species recorded in my 

 last paper, as I suspected, Porcellana priocheles appears to be one of the 

 young states of P. longicornis ; Pagurus Eblanensis I strongly suspect 

 is the true P. Ulidianus of W. Thompson ; and Portunus carcinoides 

 (Plate IX., Fig. 3, a, b, c) is a good species ; it comes very close, how- 

 ever, to Otto's P. infr actus, which is included by Bell among the syno- 



VOL. IV. Y 



