554 TEST ACE A ATLANTIC A. 



Genus 8. PUPA, Drap. 



( Gastrodon, Lowe.) 



Pupa umbilicata. 



Pupa umbilicata [var.], Drap., Tabl. des Moll. 58 (1801) 

 Helix anconostoma, Lowe, Cambr. Phil. S. Trans, iv. 62. 



t. 6. f. 30 (1831) 



Pupa anconostoma, Id., Proc. Zool. Soc. Land. 208 (1 854) 

 Alb., Mai. Mad. 61. t. 15. f. 19-22 



(1854) 

 Morel., Hist. Nat. des Acor. 198 



(1860) 



umbilicata, Paiva, Mon. Moll. Mad. 120 (1867) 

 anconostoma, Mouss., Faun. Mai. des Can. 123 



(1872) 



umbilicata, Melliss, St. Hel. 122 (1875) 

 Watson, Journ. de Conch. 223 (1876) 



Habitat in intermediis insulse, prsecipue cultis; vulga- 

 tissima. 



It is under its rather smaller form (with a less developed 

 ventral plait), which was described by Mr. Lowe as the P. an- 

 conostoma, that this common European Pupa occurs at St. 

 Helena ; and it is this particular aspect of the shell, which how- 

 ever passes by imperceptible gradations into the normal one, 

 which abounds so greatly in the Madeiran, Canarian, and 

 Azorean archipelagos : indeed I am extremely doubtful whether, 

 Pfeiffer's P. Dohrni, from the Cape Verdes, is more in reality 

 than another slight geographical modification of the selfsame 

 type. 



We may be almost sure that the present Pupa must origi- 

 nally have been introduced into the island, perhaps in the earth 

 used for the packing of shrubs and plants ; but, be this as it 

 may, it now absolutely swarms in the intermediate cultivated 

 districts, such as Plantation, Thompson's Wood, &c., where, 

 while sifting for Coleoptera, I have taken it in countless multi- 

 tudes. The first St. Helena notice of it with which I am ac- 

 quainted was by the late Mr. Benson (Ann. Nat. Hist, for April, 

 1851 ; and for December, 1856), who met with it in 1832 ' be- 

 tween Plantation House, and Stitch's Ridge ' ; and it was found 

 subsequently by Mr. E. L. Layard, while halting at the island 

 en route to the Cape of Good Hope, c under stones, in damp 

 places, about Napoleon's Tomb.' Mr. Benson was inaccurate 

 when he cited it as ' the smaller variety of the Pupa ancono- 

 stoma, Lowe,' for it is the regular and typical state of that 



