I8C8.] MR. NEVILL ON THE LAND MOLLUSKS OF MAURITIUS. 259 



This species, there is every reason to believe, will become extinct 

 in a few years. 



GiBBUs (Gibbulina) bacillus, Pfr. 



This species has the foot yellow, with a black band along the 

 sides, which is broader on the posterior part; the tentacles are 

 crimson. 



Mauritius. Arboreal. 



GiBBus (Gibbulina) teres, Pfr. 



The animal is nearly pure white, delicately spotted on the foot 

 with minute pale scarlet dots ; the tentacles are at first scarlet, then 

 dull purple. 



Mauritius. 



Gibbus (Gibbulina) holostoma, Morel. 



The foot is vivid orange, with broad black bands on each side ; 

 the tentacles are orange tipped with black. 

 Mauritius. 



Gibbus (Gibbulina) productus, H. Ad. 



The foot in this species is yellowish flesh-colour, the sides beino- 

 mottled with brown ; the tenta'cles are at first dark brown, and then 

 bright scarlet. 



Mauritius. 



Gibbus (Gibbulina) modiolus, Fe'r. 



The animal is brownish red, having the sides dark brown ; the 

 tentacles are red ; and the sole of the foot is pale greenish flesh- 

 colour. 



Mauritius. 



Var. Fuscus. 



The upper surface of the foot is brick-red, bordered with a dull 

 light-brown band, narrow on the anterior, and broad on the poste- 

 rior part ; the sole of the foot is of a dull greenish colour ; the ten- 

 tacles are brown. Arboreal. 



Gibbus (Gibbulina) striati-costa. Morel. 



The foot in this species is black, mottled with orange, and with 

 an orange fillet round the base and down the middle of the upper 

 surface of the posterior part ; the sole of the foot is pale orange 

 flesh-colour. 



Mauritius. Found living on the ground. 



This species is consistent in its colouring, and is very striking in 

 appearance. 



Gibbus (Gibbulina) callifer, Morel. 



The sole of the foot of the animal is greenish flesh-colour, the 



