644 C. H. MARTIN. 
form individual. In one of Milne’s figures, three of these 
structures are shown, and in another eight, but on the only 
occasion on which I examined a living Ophryodendron 
trinacria I saw no trace of these structures. 
It is now necessary to refer to a rather remarkable state- 
ment by Sand that the vermiform individual of Ophryo- 
dendron belgicum is attached, not by a rod-hke stalk but 
by a tentacle (p. 336). ‘ Le pedicule du Lagéniforme est 
chez cette espéce un tentacule ordinaire capité, analogue a 
celui un suceur quelconque.” This species was first found 
by Fraipont and it is rather remarkable that no mention is 
made in his long account of Ophryodendron of this remark- 
able structure. 
Saville Kent remarks (p. 855) that “apart from its size 
(Ophryodendron abietinum, P. 1.75’—1.30”.  V. 
1:50” to 1.307% ©. beleicum, P. 14007. V. 1.4007) Famd 
habitat (O. belgicum is described as occurring on Clytia 
volubilis) the chief distinction between this type and O. 
abietinum would seem to subsist in the less luxuriant deve- 
lopment of the tentacular appendages of the proboscis.” 
Biitschhli also believed that the species Ophryodendron 
belgicum was identical with Ophryodendron abie- 
tinum. I myself worked partly on a form occurring on 
Clytia and partly on a form occurring on Obelia, and 
could find no essential difference between them and until 
further evidence is adduced than Sand’s Pl. 13, fig. 9, it 
would seem impossible to credit this very abnormal state of 
affairs, especially as the structure figured looks far more like 
a stalk than a tentacle. 
6. THe FrEDING Or OPHRYODENDRON. 
Ophryodendron abietinum is to a very large extent a 
true external parasite of the hydroid to which it is attached, 
as will be shown by the observations on the living animal 
detailed below. I have, however, on two occasions, seen it 
