454 TEST ACE A ATLANTIC A. 



Indeed, out of the many examples of the genus Pupa which I 

 sent to him for inspection, the P. castanea was not included 

 (for I did not at that time even possess it) ; and yet my nume- 

 rous individuals of the nearly-allied form (from Teneriffe, Palma, 

 and Hierro) which he defined as the P. pythiella were returned 

 to me as partly referable to the latter, and partly to the cas- 

 tanea, with such an extreme amount of indecision that I failed 

 to recognize any distinctions between them. But now that 

 what is manifestly Shuttleworth's true castanea has come into 

 my hands, I can no longer entertain the slightest doubt that the 

 two species are distinct. 



As compared with the pythiella, the P, castanea is appre- 

 ciably larger, broader, and more strictly ovate (or less oval), as 

 well as more coarsely striated ; its whorls are more convex (and 

 the suture consequently deeper), and its aperture is more widely 

 developed and more auriform, the margins of its peristome 

 (which is thicker, and of a more livid or carneous tinge, or less 

 white) being much wider apart, and the right-hand one more 

 outwardly-rounded below the insertion, as well as armed with a 

 more distinct tubercle within. Its upper ventral plait, also, is 

 more lamelliform and less sinuated, and not only a little further 

 removed from the angle of the lip, but usually quite uncon- 

 nected with the latter by a corneous sphincter. 



Mr. Lowe's examples of this very distinct Pupa were taken, 

 during April of 1861, above Grarachjco, in the north of Tene- 

 ritfe, namely adhering to wet rocks and sodden leaves, in the 

 drip of a small waterfall, on the road from that place to Ycod 

 de los Vinhos (in company with the Hyalina Clymene, Physa 

 acuta, Ancylus striatus, and Hydroccena gutta, the moisture- 

 loving habits of which it would appear to share). 



Pupa pythiella, 



T. prsecedenti affinis, sed minor, angustior, magis ovalis (sc. 

 minus ovata), ac sensim levius striata; anfractibus minus con- 

 vexis (ergo sutura magis superficiali); apertura minore, angus- 

 tiore, margine dextro multo minus exstanti-rotundato, et intus 

 obsoletius tuberculiformi, plica ventrali superiore crassiore, 

 magis sinuata, et ssepius cum angulo sphinctere juncto (quare 

 sinum evidentius efficiente), columellari subminus obliqua, 

 necnon peristomate albidiore minusque expanse, marginibus 

 minus remotis. Long. lin. 11^. 



Pupa pythiella, Mouss., Faun, Mai. des Can. 127. pi. 6. 



f. 22, 23 (1872) 

 Pfei/., Mon. Hel. viii. 389 (1876) 



