452 PYRAMIDELLIDA. 
the Chemnitzie, which are not seen in the fully adult £. 
polita. 
With respect to the tentacula, we may state, that in all the 
young E. polita, under half an inch in length, they are quite 
white and the arcuated yellow lines in front of the foot are 
wanting ; they are also flatter, with rudimental flake tips ; but 
with age all these young incidents disappear. All the Hulime 
are more or less distorted or arcuated posteriorly, but increase 
of growth diminishes the effect of what is so apparent in the 
young shell. 
The operculigerous lobes of the animal are as unequal as in 
E. polita. The foot of this minute example appears propor- 
tionately more slender and hyaline than in the adult; it has 
a labium well separated from its upper skin, which some 
authors call a mentum ; but, even admitting that term, the 
organ is very different from that continuous neck-production 
in the Chemnitziea, which we have styled a rostrum, and M. 
Loven the mentum. 
The animal is extremely free and vivacious; it delights in 
swimming, and marches with far more celerity than the adult 
E. polita. Axis of the specimen examined -2,, diameter -!; 
unciz. It is found plentifully in company with the EL. polita, 
and that variation termed EF. nitida by the Scotch naturalists, 
in the coralline zone at Exmouth, and off Teignmouth, in a 
fine muddy and shelly bottom, in 14 fathoms water. 
The following have not occurred to me alive :— 
E. susuxtata, Donovan. 
E. subulata, Brit. Moll. iii. p. 235, pl. 92. f. 7, 8. 
E. pitineata, Alder. 
E. bilineata, Brit. Moll. ii. p. 237, pl. 92. f.9; (animal) pl. K.K. f. 5. 
We believe that the latter is the young of the former. 
ACLIS, Lovén. 
This genus contains only two very rare British species, the 
Turbo ascaris of Turton and the A. supranitida of S. Wood ; 
