400 KJERSCHOW AGERSBORG 
This seems to be a conclusive proof that Clione limacinct 
Phipps bas ciliated grooves sometimes in its life. But even 
though this may be the case, it is not a proof against the fact 
that adults of this genus, or family, of the mollusks, may not 
be tri-trichocycliated as in the case of C. kincaidi^ or other 
members of the same family, but of a different generic rank, 
may be indeed also tri-trichocycliated, as in the case of 
Trichocyclus hansineënsis. More than 100 specimens of 
C. kincaidi which 1 examined had ail only one of the ciliated 
circles, viz., the posterior one. It was not always, however, ^ 
in such a condition in the same individual to be visible. 
Sometimes I was unable to detect any cilia in the ciliated 
groove of the same individual of Clione^ but at other 
times they were asily seen. In specimens preserved in 
10 o/o formaldéhyde, the cilia cannot be seen on the speci¬ 
mens although magnified 30 times^. C, kincaidi resemblei^ 
the other members ot the genus in many respects, but it dih 
fers from the other members in several points; the foot is 
quite different; the mesopodium is pointed anteriorly instead 
of posteriorly; it is smaller than in C. limacina. The cha- 
racteristic presence of a posterior ciliated groove marks its 
peculiarity and shows its affinity to C. limacina. In color 
and shape, it is different from C. elegantissima and C. dalli. 
The différence between Clione kincaidi and Trichocyclus 
hansineënsis is very markedboth on their method of swimm- 
ing and in the general form of their body that there is no 
need of ever confusing the two with one another, or to classify 
Trichocyclus with any of the other généra as previously done^ 
Trichocyclus hansineënsis is a member of the family Clionidæ 
Gray (1840) because it conforms with the description of this 
family. But it is a new genus., and I hâve employed the ori¬ 
ginal nomenclature of Eschscholtz (1825) although Esch- 
scholtz's formmay actually belong to another genus. In 
fact, Eschscholtz's type has been emerged with ClionopsiSy 
and the name discarded on the ground that « it is not a good 
one, )) by the authors since they think Trichocyclus is a larva. 
And, the members of this school, maintain this daim even 
for sexually mature tri-trichocycleated forms. But this, of 
