454 TEST ACE A ATLANTICA. 



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

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

 (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 Grarachico, in the north of Tene- 

 riffe, — 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 Hydrocoina 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 expanso, marginibus 

 minus remotis. — Long. lin. \—\\. 



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

 f. 22, 23 (1872) 

 „ „ Pfeig., Mon. Hel. viii. 389 (1876) 



