64 ROYAL SOCIETY OF CANADA 
de la quatrième espèce; and I have elsewhere (1901) pointed out that it 
has also been described by Tilesius (1809) as À. priapus and possibly 
by Brandt (1835) as A. farcimen. The terms marginatum and fim- 
briatum applied to American representatives of the species have already 
been mentioned. 
More serious, however, than this multiplication of names was the 
confusion that arose in the application of the Linnean terms. This 
began very early, for Baster in the explanation of his figures describes 
fig. 2 of Pl. XIII (the figure of M. senile) thus:—‘ Priapus sive Actinia 
proboscidibus tenuibus brevibus; Priapus equinus dicta.” That is to 
say, he identified the species under consideration with that described by 
Linnæus in the Systema Nature Ed. X as Priapus equinus, which 
Linnæus himself regarded as quite distinct from his Actinia senilis. 
O. F. Müller in the discussion of the synonomy of his A. rufa (1788), 
which is identical with the form usually known as A. equina, suggests 
that if one considers the specific descriptions of A. senilis given by 
Linnzeus, rufa may be identical with that form; but if the synonyms of 
Linnæus be considered this is less probable. Bruguière, however, 
accepted Müller’s suggestion and made A. senilis identical with A. rufa, 
an error in which he was followed by Bosc (1802). 
More frequent, however, has been the identification of Linnæus’ 
A. senilis with the form usually known as Urticina crassicornis (O.F.M.), 
whose correct name will be discussed later. The first step towards the 
establishment of this confusion was taken by Linnæus himself in men- 
tioning Stroem’s Sdekuse as a synonym for senilis, and this was followed 
up by Bishop Gunner describing in 1767 as A. senilis a form which is 
quite evidently U. crassicornis. Further, it would seem that the form 
identified as senilis by Fabricius in 1780 was also crassicornis, and that 
described by Dicquemare in 1773 as his seconde espéce, again evidently 
crassicornis, was identified by Solander as the senilis of Linnæus. 
Gmelin in the XIII Ed. of the Systema Nature gives A. senilis as a 
synonym of A. crassicornis, and Oken does the same in his Lehrbuch 
(1816), and in his Allgemeine Naturgeschichte published in 1835, he 
describes crassicornis as A. senilis. Cuvier in his Régne Animal (1817), 
gives A. senilis as a synonym of his A. coriacea, which again is identical 
with Müller’s crassicornis, and this synonomy was very generally ac- 
cepted by subsequent authors, as, for instance, by Rapp (1829), Ehren- 
berg (1834), Hollard (1848 and 1854), and Milne-Edwards (1857). 
This confusion, it may be added, has been somewhat aggravated 
by Andres (1883), who describes the species under consideration as 
Actinoloba dianthus. His reasons for rejecting the generic term Metri- 
dium will not, however, hold, and he further seems to have fallen into 
some errors in his interpretation of the Linnaean specific names. Thus he 
