SLUGS. 85 
cella) (Pl. VI., fig. 38).—This slug is of a dirty 
yellow colour, sometimes uniformly black, rarely 
pale yellow; spotted with brownish specks, mixed’ 
with pale orange along the margin of the foot ; 
and is furnished with a small roundish oval shell, 
with a minute spire at the end of the tail (see 
fig. 14), which covers the mantle. A lateral 
furrow commences from near the tip of the shell 
by a double wavy line on both sides of the body, 
dividing the lateral portions of the animal in two 
unequal parts, until it terminates near the head. 
The surface of the body is granulated. This 
slug exhibits, as it were, a third pair of ten- 
tacles, by the protrusion of the corners of the 
lip ; they resemble, but are scarcely so long as, the 
pair of tentacles abovethem. See fig. 14, show- 
Fig. 14.—Testucellu haiiotidea. 
ing a front view of the head; the centre figure 
represents the back view of a half-grown indi- 
vidual; the other, a side view of the shell on the 
tail; the respiratory orifice is also seen. 
When crawling, the Testacella is about three 
inches in length. 
The shell is oval, ear-shaped, depressed, 
rugous; striated in the lines of growth. Epi- 
