40 TEST ACE A ATLANTIC A. 



base of the walls. It is compared by Morelet to the common 

 European B. oliscurus; but it is a little larger and more ven- 

 tricose, and its peristome is more obtuse and thickened. It 

 seems to be very variable in stature, its extreme length mea- 

 suring from about 9 to 11 millimetres. 



Morelet calls attention to a shell which exists on the moun- 

 tains of S. Miguel, in the neighbourhood of the Lagoa do 

 Congro, which is so strictly intermediate between the B. vulgaris 

 and praiiuius (the types of which are otherwise altogether dis- 

 similar) that he is quite unable to decide to which of them it 

 should be referred ; and he consequently arrives at the con- 

 clusion that, in all probability, it is a hybrid between the two 

 species. 



Bulinms delibutus. 



Bulimus delibutus, Morel, et Dr., Jov/rn. cle Conch, vi. 151 



(1857) 

 „ „ Mouss., Viert. der Nat. Zurich, 167 



(1858) 

 „ „ Pfeiff., Mon. Hel. iv. 474 (1859) 



„ „ Morel., Hist. Nat. des Acor. 190. t. 4. 



f. 4 (1860) 

 „ „ Drouet, Faun. Agor. 161 (1861) 



Habitat Terceira, et Fayal ; hinc inde in saxosis oscurrens. 



The B. delibutus, which has been found in Terceira and 

 Fayal, seems to be very near to the vulgaris, — from which it 

 mainly differs in being a trifle slenderer and more shining, and 

 in having its suture obscurely and very narrowly edged with 

 white. It appears also to be more or less lightly marked with 

 spiral undulating lines, sometimes paler and sometimes darker 

 than the ground-colour, but which are apt to become obsolete 

 when the shell happens to be thinner than usual and more 

 transparent. The columellary edge of its peristome is just 

 appreciably wider than is the case in the B. vulgaris, and has a 

 very slight tendency to be subrecurved. 



Bulimus Forbesianus. 



Bulimus variatus, Bunk, [nee W. et B., 1833], hid. Moll. 



6. t. 1. f. 24, 25 

 „ „ Pfeif., Mon. Hel. iii. 355 (1853) 



„ Forbesianus, Morel, et Dr., Journ. de Conch, vi. 



151 (1857) 

 „ atlanticus, Mouss., Viert. der Nat. Zurich, 166 



(1858) 

 „ Forbesianus, Pfeiff., Mon. Hel. iv. 422 (1859) 



