FAMILY 4. TUBISPIRACEA. 45 
VERMETUS, Adanson. 
Testa tubulosa, subcylindrica, irregulariter contorta, posticé plerumque 
attenuata, in spiram laxatam sepissimé producta, anticé evoluta, 
interdum erecto-undata ; interne septis interdum divisa, apertura 
rotunda, simplici. Operculum corneum, concavum. 
The genus Vermetus, proposed by Adanson, was rightly placed by him 
with the Mollusca, and may be remarked as affording another instance 
of how much Linneus might have profited in his arrangement of the 
‘Systema Nature,’ if he had given more attention to the discoveries of 
this intelligent traveller. The alterations and amendments of this na- 
turalist, though established upon actual observation, were no doubt 
looked upon by our great author as both dangerous and unnecessary. 
It was some time before even Lamarck appreciated the arrangement of 
Adanson, for the genus under consideration was originally referred by 
him to the Serpulaceous Annelides, under the appellation of Vermicu- 
laria ; the title of Vermetus was afterwards restored by De Roissy, and 
Lamarck was forced to acknowledge the propriety of observing it. Cu- 
vier appears to have been the first to have followed Adanson in placing 
the Vermeti with the Mollusca ; and the only opinion upon which authors 
are now divided is as to whether they approximate to the Siliquarié or to 
the Scalarie. The animal has been recently described and figured both 
by Quoy, and d’Orbigny. 
The shell of Vermetus may be described as being tubular, subcylin- 
drical, and irregularly twisted ; the posterior end is generally attenuated, 
and most frequently produced into a loose spire ; the anterior is unrolled, 
and sometimes erect ; the interior of the shell is often divided by trans- 
verse septa, and the aperture is round and simple. The operculum is 
horny and concave. 
