THE LAND AND JBESHWATER MOLLUSCA OF DORSETSHIRE. 101 



and heart, which are placed in the tail region instead of the 

 anterior part of the body. This provision affords the outer air 

 free access to the lungs when the animal is in pursuit of its 

 prey through the narrow subterranean channels of the earth- 

 worm, which is its principal food. These delicate organs are 

 protected by a small shell, flattened and lying nearly parallel to 

 the axis of the body, so as to interfere as little as possible with 

 the free movements of the animal in its underground progress. 



The head is small, with two large and two small tentacles ; 

 its large mouth is furnished with several rows of recurved 

 teeth; the jaws are enormously strengthened by a powerful 

 muscle which extends through the whole length of the body, and 

 is attached to the left posterior side by several fleshy attach- 

 ments ; the lips have the power of protrusion, so as to give them 

 the appearance of tentacles. 



1. TESTACELLA HALiOTiDEA, Dmparnaud. 



Body contracted towards the front, and somewhat pointed at the 

 head; smaller in the middle, thicker and rounded behind, capable 

 of extending itself as long as five inches ; the skin is tough and 

 thick, more so than the Arions and Limuces. Two longitudinal 

 grooves commencing at the anterior border of the shell and 

 extending: to the neck, enclose the greater portion of the back, 

 which is furrowed longitudinally and obliquely by smaller and 

 shallower grooves. Near the head these are replaced by rugosities, 

 which become indistinct when the body is extended. The colour of 

 the body is reddish-brown, more or less spotted with red, black, 

 and white; mantle very small, scarcely exceeding the shell; 

 tentacles, short in proportion to the Arions and Limaces, the upper 

 are slightly swollen at the extremities; colour similar to the rest of 

 the body; eyes placed near the upper extremity, and slightly on the 

 exterior side. L.3. B.0.4. 



Shell oblong, ear-shaped and compressed, especially in the 

 middle, and front margin ; contracted towards its posterior end, 

 which is curved backward with a slight projection, invisible when 

 viewed from above ; colour dirty white, opaque, with an epidermal 

 covering with several successive concentric lines of growth; the 

 nterior is smooth and glossy ; mouth exceedingly large, the 

 anterior mat gin rounded, the posterior obliquely truncate. L.0.25. 

 B.0.15. 



Gardens, Down House, Blandford (Sir W. Smith-Marriott). 

 Stalbridge, Stfence Gossip, 1877, p, 209, 



