324 



THE YOUNG NATURALIST. 



AcutllS. — This is the prettiest shell of 

 the genus, it is conical, measuring more than 

 half-an-inch in length, and less than a quar- 

 ter of an inch in diameter at the broadest 

 part. It is a thin light shell, whitish, with 

 brOwn markings, whorls rounded and wrin- 

 kled, with a dark brown band roup d the base, 

 It is found in the south-west of England, 

 near the sea, where it is abundant. 



Monoanus. — This shell resembles the 

 preceding in shape and size, but is of a 

 brownish color without markings. It is a 

 local species found about woods in the south 

 and west of England, and is called by some 

 conchologists Lackhamensis . 



Obscurus. — The shell of this species is 

 smaller than the others, it is similar to the 

 last in color, the whorls being a little more 

 prominently rounded, the lip is white. It is 

 more generally distributed than Montanus, 

 and is found about old walls, under stones 

 and moss, &c. 



Genus, Zua, 



This genus resembles Bulimus, except that 

 the shell is very bright and polished. There 

 is only one species, Subcylindrica. 



Sub oylindrica. — The shell is much 

 smaller than any of the Bulimi, being little 

 more than a quarter of an inch long, it is 

 similar in shape, but with the spire rather 

 blunter, it is smooth and glossy, without an 

 umbilicus, and with a small aperture. It 

 may be found under stones, decayed leaves, 

 Sec. 



Genus, Azeca. 



In this genus the shell is very similar in 

 shape to that of Zua, but it approaches more 

 nearly to an oval, and the aperture, which is 

 small, is distinctly toothed within. Tridens is 

 the only species we have in this country. 



Trie 3ELS. — The shell is oval and pupa- 

 iike in form, the spire being rather blunt, 

 and the aperture small and contracted, there 

 is no umbilicus, the lip is continuous round 

 the aperture, within which are three distinct 

 teeth, readily distinguishing it from Z . sub- 



cylindrica, which it resembles in size, and in t 

 its smooth shining surface. It is found about 

 woods, but is not a common species. 



Genus, Achatina. 

 This is another genus in which we have 

 only one small British species, the shell is 

 very narrow, with smooth flattened whorls. 

 The animal is white. The species is named 

 Acicula. 



Acicula. — This little shell measures 

 scarcely a quarter of an inch in length, and 

 only about one-fourth as much in diameter. 

 The spire tapers regularly to the apex, which 

 is rather blunt. It is without an umbilicus, 

 there is a notch on the inner portion of the 

 lip. It is smooth, white, and transparent. 

 It may be found under stones, or concealed 

 in loose earth, but it is not an abundant 

 species. 



Genus, Clausilia. 



The animal of this genus does not differ 

 much from those of several of the preceding 

 genera, there are, however, important dis- 

 tinctions in the shell, this is long and taper- 

 ing, the whorls reversed — that is coiled in 

 the opposite direction to those of most shells, 

 without an umbilicus, aperture small with 

 internal teeth ; within the shell is a small 

 door, or clausiliiim, which is hinged to the 

 columella, and closes by the elasticity of the 

 hinge when the animal retires into its shell, 

 and opens by the pressure from within when 

 it wishes to emerge ; this clausiliiim is a shelly 

 plate corresponding in form to the aperture, 

 and attached to the shell, not to the foot of 

 the animal like an operculum. There are 

 four species inhabiting this country, Laminata, 

 Biplicata, Rolphii, and Perversa. 



Laminata. — This shell, which is nearly 

 three-quarters of an inch long, when full- 

 growr , is somewhat club shaped, being 

 broadest towards the base, and the spire long 

 and narrow, the lip is continuous round the 

 aperture, and there are two distinct teeth 

 within ; it is brown, or yellowish in color, 

 smooth and transparent. It is found in 



