134 TELLINIDA. 
larger diameter, and when protruded is barely an inch in 
length; its extremity is furnished with 12-15 white, short 
cirrhi, of more uniform length than in the branchial; it has 
not the dark terminal margin of poimts: the usual hyaline 
valve was not observed, but it probably exists. 
This siphonal apparatus has the entire aspect of that of the 
typical Tellinide ; but its position when exserted is singular, 
' being very little posterior to the centre of the ventral range, 
instead of being, as is more usual, protruded from a posterior 
angle somewhat more basal than a right one to a vertical line 
drawn from the beaks to the ventral centre; this nearly central 
basal site is occasioned by the great size and low position of - 
the posterior adductor, which necessarily compels the issue I 
have described. 
The foot is white, not large, flat, bevelled, pointed, very 
little geniculated, without a byssal groove, scarcely differing 
from the Telline and some of the Veneres; it also, from the 
causes assigned to the siphons, has a more basal position than 
usual when protruded, with a very limited anterior action, 
from which it may be inferred that the motive power is con- 
fined to the turning from side to side and on its centre. The 
branchiz are subcircular, the upper plates bemg much less 
than the lower, half lappmg on them, pale drab, with mode- 
rately fine but not very distinct pectinations ; the pair of palpi 
on each side are fleshy, rather long, triangular, pointed, 
strongly pectinated on the outsides, smooth within, and con- 
nected with each other around the mouth; they are also light 
drab. The body is pale pink, small and subglobular, having 
the foot fixed to its centre. The liveris grass-green. I have 
already alluded to the texture of the shell, but it is necessary 
to add, that in the right valve there are two laminar primary 
teeth, and in the left two similar ones, with a strong double 
tooth between them: there are no laterals. 
It would then appear, that the texture of the shell, the two 
laminar teeth in the right valve, and the exact similitude to the 
typical Telline, of the very long, slender, divergent siphonal 
apparatus having each tube completely separated to the base, 
ally this animal by many degrees nearer to the Telinide than 
