216 J- Playfair Mc Müeeich, 



wlio in 1878 made known a couple of Patagonian forms collected by 

 tlie "Gazelle", and by Ridley, who reported in 1881 on tlie coelen- 

 terata collected by the "Alert", during a survey of the Straits of 

 Magellan. 



The descriptions of tliese authors are, liowever, also more or less 

 incomplete, and it is not until 1882 and 1888, when the Actiniaria 

 of the "Challenger" Expedition were described by Richard HERTwia, 

 that attention was given to the anatomical details of South American 

 actinians. In 1893 I published a report on the forms obtained by 

 the "Albatross" during a voyage from New York to San Francisco, 

 and in 1896 Kwietniewski published a revision of the forms previ- 

 ously described by Studer. Finally in 1899 Carlgren gave in a 

 preliminary form his observations on the species collected by the 

 "Eugenia" Expedition (1851 — 53), the German South-pole Expedition 

 (1882—83), the Hamburg Magellan Expedition (1892—93) and the 

 Swedish Expedition to Tierra del Fuego (1895—96). 



The Plate coUection compared with most of its predecessors 

 is rieh both in individuals and species and contains representatives 

 from various localities along the coast from Iquique on the north 

 to Punta Arenas on the south. It has yielded important re- 

 sults in Clearing up with a considerable amount of certainty the 

 identity of some of the forms described by earlier authors, and by 

 perfecting our knowledge of the Chilian fauna by the addition to it 

 of a number of forms it has served to confirm our previous ideas 

 as to the general characters of the actinian fauna of this coast, so 

 excellently expressed by Carlgren (1899). 



Order Actiniaria (Dana) Van Beneden. 



The term Actiniaria has been used by diiferent authors with 

 somewhat diiferent limitations. It was introduced by Dana (1846) 

 as a suborder of Actinoidea and included all the Anthozoa (includ- 

 ing Lucernaria) with the exception of the Alcyonaria. Milne- Ed- 

 wards (1857) employed the term as an alternative for his Zoan- 

 tharia malacodermata, a group which excluded all forms possessing 

 a deflnite corallum and also Lucernaria. In this sense it was at first 

 employed by Verrill (1864), although in a later paper he re-included 

 the Antipatharia in the group. 



In 1870 Gray still further reduced the contents of the group 

 by separating from it the Zoantheae, an arrangement followed later 

 by Klunzinger (1877). Andres (1883) returned to the use of the 



