SERPULA. 447 
Serpula avenarta. 
Before the separation of the S. polythalamia as a distinct 
species, in the twelfth edition of the ‘Systema,’ the figure of 
that gigantic tube had been quoted by Linneus in illustration 
of the present shell: hence ensued that most inappropriate 
epithet arenaria, the name appended to the engraving of Rum- 
phius. It might, perhaps, have been expected that the appella- 
tion would have been transferred to polythalamia, along with 
the illustration, but the “subangulata” of the tenth edition 
(changed eventually to “subtus planiuscula,”’ indicative of the 
shell being sessile or attached) did not permit of it; that 
feature, a characteristic of the Vermeti delineated by Gualtier 
and Bonanni, not being present in the free cylindrical Septaria. 
The Indian habitat, apparently derived from Rumphius, was 
erroneously retained in the twelfth edition, when the figure 
itself had been withdrawn from the synonymy. The meagre 
antithetical description, to which “ Lumbrici instar contorta, 
rarius spiralis, raro extus articulata” has been appended in the 
revised copy, is applicable to all the Vermeti included in the 
synonymy. ‘The drawings of Bonanni represent the Vermetus 
gigas of the Mediterranean, for which, likewise, those of Gualtier 
have been quoted by Philippi, and although the figure N is de- 
picted as more strongly sculptured than is usual, it is not so 
unlike the finer examples. On these grounds has the identity 
of that shell with the Serpula arenaria of the ‘ Systema’ been 
suggested, and with reason, for a specimen of it (Philippi, Moll. 
Sicil. vol. i. pl. 9, f. 18) is still preserved in the cabinet of 
Linneus (who has recorded his possession of an example of 
arenaria), and alone answers to the definition of the species. 
Argenville’s drawing (copied by Martini as figure 19, A of his 
third plate) seems the spiral commencement of another Ver- 
metus (perhaps a solitary triqueter), but is not known to me; it 
was (wisely ?) passed over in the tenth edition, and as we learn 
from the “rarius spiralis,” was not to be regarded as the typical 
or more characteristic form. 
The “szpe in duos ramos bifida” of the ‘Museum Ulrice,’ 
where the very dissimilar figures of Gualtier and Rumphius 
