26 Proceedings of the Royal Irish Academy. 



the Marine Mollusca of Ireland " (Proc. Roy. Irish Acad. (3), v., 

 1900) and on "Irish Echinoderms " (Proc. Roy. Irish Acad., xxiv., 

 Sect. B., 1903), namely:— 



i. North-east. — Prom Malin Head, Co. Donegal, to St. John's Point, 

 Co. Down. 



ii. East. — From St. John's Point to Carnsore Point, Co. Wexford. 



iii. South. — Prom Carnsore Point to Cape Clear, Co. Cork. 



iv. South-west. — From Cape Clear to Loop Head, Co. Clare. 

 V. West. — From Loop Head to Erris Head, Co. Mayo. 



vi. IN'orth-west. — From Erris Head to Malin Head, Co. Donegal. 



The classification of the Hydroids is based on that proposed by 

 K. C. Schneider in his paper on the " Hydropolypen von Rovigno, 

 nebst TJebersicht des Systems der Hydropolypen im AUgemeinen " 

 (Zoologische Jahrbiicher, x., 1898), while the Medusae are arranged 

 according to Haeckel. The Hydroids and Medusae are kept quite 

 distinct, as any attempt to combine them would create too much con- 

 fusion in a list of this kind ; when possible, however, the Medusa is 

 given the name belonging to its Hydroid. The arrangement of the 

 Anthozoa is taken from Professor Ray Lankester's " Treatise of 

 Zoology," Part II. The nomenclatui'e and synonomy of the Sea- 

 anemones, especially, is still in a very unsatisfactory state. 



Very few Ctenophora occur off our coast ; they are included here, 

 although attempts have lately been made to class them with the 

 Turbellarian worms. 



The Hydroids of the Irish Coast belong, for the most part, to widely 

 distributed species, some of them having been recorded for ^N'orth 

 America, India, Australia, and liew Zealand. On the other hand, 

 Tuhiclava lucerna, T. cornucopm, and HeterocordyU conyhearei have 

 been recorded for two, or at the most, three localities ; while Perigo- 

 nimus gelatinosus^ P. inflatus^ and Campanulina turrita seem to have 

 been found hitherto only ofE the Irish coast. The fresh-water Hydroids 

 are very few in number, namely Cordylophora lacustris and three 

 species of Hydra, and are included in this list. 



Our knowledge of the Medusae of the south-west of Ireland is 

 almost entirely due to Mr. E. T. Rrowne ; while Professor Haddon, 

 working chiefly at the material collected during several Royal Irish 

 Academy Expeditions, has added some Sea-anemones to the British 

 Fauna : — Edwardsia [tecta, Hcdcampa arenarea, Ein%oanthu8 wrightii^ 

 Pa/ra%oanthus dixoni, Chitonactis marioni, Paraphellia expansa, Gephyra 

 dohrnii^ and a species of Actinerus, 



