APPENDIX. 525 
clavate or hammer-like appearance, becoming thick, angular, 
bevelled to a sudden edge, straight in front, without auricles 
or central indentation. The tentacula are very short, and 
their tips less marked and folded than in-many others of this 
tribe. 
CHEMNITZIA CLAVULA.—(P. 436.) 
Exmouth, July 1854. 
After a lapse of two years, a single, beautiful, lively specimen 
of this rare species has been met with, which enables me to 
say’that the original notes are correct; I can only add a few 
minor particulars, which might have been neglected, had I 
not wished to give naturalists the means of verifying decisively 
this elegant and very scarce creature. 
The tentacula are extraordinarily short and broad, in con- 
sequence of the auricular portions that spring from their 
external margins unfolding and forming a large, fine, arcuated 
membranous leaf, that terminates just under the apical in- 
flations. 
The foot on the march, when the animal is agitated, can be 
pushed into longish auricles, and in consequence shows a con- 
siderable curved hollow in front; this fact is common to all 
the Chemnitzie, but in deliberate progression it becomes trun- 
cate with subdued angular points; the posterior extremity in 
the example observed was slightly emarginate on the right 
and left sides, giving the central portion the aspect of a 
rounded or blunt stylet. On each side of the foot, when the 
animal is in motion, there is a marginal series of about ten 
very minute glossy pots. 
This beautiful creature was remarkably free, and allowed 
me to sce the fine line of the proboscidal fissure on the ros- 
trum immediately below the eyes. It was taken in the same 
habitat as the original examples. 
I have omitted to state above that the foot is constricted 
gradually below the auricles ; it is not narrow, and can, on the 
full march, be extended to the second basal volution : when 
that happens, its posteal emarginations nearly vanish. 
The apical reflexion of the shell is less pronounced than 
