CAPE-VERDE GROUP. 615 



I am not aware that it has been observed as yet in any of the 

 other islands. 



I may just remark, however, that if the P. Dohrni is to be 

 regarded as specifically distinct from the ' var. @. anconostoma ' 

 of the P. umbilicata, the S. Antao examples must be accepted 

 as more typical than those from S. Nicolao ; for not only are 

 they a trifle more widened behind, but their ventral plait is 

 smaller and more completely disconnected with the angle of the 

 lip, and the peristome is browner. Indeed the S. Nicolao 

 specimens, in their general contour and more enlarged and more 

 triangular plait, are well-nigh inseparable from the 'var. (3. 

 anconostoma ' of the P. umbilicata ; and I suspect that it is 

 owing to this very circumstance that Morelet has recorded the 

 P. anconostoma (in addition to the Milleri or Dohrni) as 

 occurring in the Cape- Verde archipelago. Nevertheless I am 

 satisfied that if the P. Dohrni is to be acknowledged as dis- 

 tinct, these S. Nicolao examples (which are in some degree 

 aberrant) must be assigned strictly to it, and not to the anco- 

 nostoma^ seeing that they possess the same peculiarity of 

 rather enlarged, posteriorly-rounded aperture which charac- 

 terizes the more normal individuals from S. Antao ; though my 

 own belief is, that the very existence of this intermediate 

 phasis from S. Nicolao (which we may cite as the ' var. a. 

 perdubia ') would tend to corroborate my original conjecture 

 that the P. Dohrni is no more, in reality, than a mere geogra- 

 phical modification of the P. umbilicata, analogous to, but not 

 exceeding (in importance), the f var. anconostoma 7 of that 

 same species. I will add that the ' var. a. perdubiaj from S. 

 Nicolao, of the P. Dohrni, has the obsolete plait on the colu- 

 mella more developed than in the type (from S. Antao), an 

 oblique columellary callosity being quite appreciable. 



( Gastrocopta, Woll.) 



Pupa acarus. 



Pupa acarus^ Benson, Ann. Nat. Hist, xviii. 435 (1856) 

 Pfeiff., Mon. Hel. iv. 686 (1859) 

 Dohrn, Mai. Bldtt. xvi. 12 (1869) 

 ,. ,5 Morel., Journ. de Conch, xiii. 242 (1873) 

 Habitat S. Antao, S. Vicente, S. Nicolao, S. lago, et Fogo ; 

 in intermediis, hinc inde (saepe sub cortice Euphorbiarum laxo 

 emortuo) congregans. 



A minute Pupa (measuring only about a line in length) 

 which is widely spread over the Cape- Verde archipelago, where 

 in all probability it will be found (like the P. gorgonica, 

 Dohrn) to occur well-nigh universally. It was first taken by 



L L 2 



