OBSBKVED AT MOGADOE. 199 



squalida or ohtecta, Lowe, instead of being regularly (with the 

 vertex) prominent or convex. The colour is a pale dull brown, 

 obscurely banded and speckled. 



Diaui. maj. 6, min. 5^, alt. 3^-3^ millim. Anfr. 4^|-. 



Found with the last species, rrr. 



6. H. lancerottensis, Webb. 



T. parvula globulosa subturbinata pisiformis perforata tenuiuscula rudi- 

 uscula striatula calcareo-albiila v. pallide fusca saepe variata s. indi- 

 stincte maculata et fasciata; spira convexa elevatiuscula depresso- 

 conoidea apice obtuse, sutura distincta impressa ; anfr. 4^-5 convexis 

 tumidiuscubs, ultimo subtus rotundato-convexo antice baud vel vix 

 deflexo ; umbilico cylindrico parvo distincto ; apertura rotundato-ovali 

 altiore quam lata parum lunata ; peristomate interrupto simplici recto 

 acuto ad umbilicum reflexo labris remotis. 



a. Webbii ; pusilla, umbilico subcoarctato angustiore. H. lancerottensis, 

 Webb. ! Syn. p. 12, No. 17 ; Hist. Can. ii. 2, 1. 1. ff.24, 25 (not D'Orb. ! 

 descr. I. c. p. 60). 



Hub. Mogador, r ; in Lanzarote and Fuerteventura less common than 

 in tbe rest of the Canary Islands. 



This is the only instance at present of the occiuTence of a purely 

 Canarian Helix on the opposite African continent. 



D'Orbigny's description (W. B. Hist. Can. I. c. p. 60) oiH. lance- 

 rottensis proves by his original single type to have been drawn up 

 from an old dead bleached example of H. monilifera, Webb ! The 

 figures, however, to which he refers (t. 1. if. 24, 25) represent the 

 true S. lancerottensis of Webb, whose first two plates of shells had 

 been engraved under his own management by Terver, long pre- 

 vious to D'Orbigny's engagement in the work, and correctly 

 exhibit the species originally intended, and published by Webb 

 in his Synopsis, but of which the present is vmfortunately not the 

 only one subsequently misunderstood and thrown into confusion 

 by D'Orbigny. 



/3. Bertheloti ; pusilla, umbiUco paullo largiore. 

 Hub. Mogador, e. 



H. Orhifjnyi, Webb in D'Orb. I. c. p. 59, t. 2. ff. 31-33 (not 

 of D'Orb.'s types !), a commonly diffused though nowhere locally 

 abundant shell in almost all the Canary Islands, and especially in 

 Teneriffe, is merely a larger more developed form of /3, and wiU 

 stand thvis : 



H. lancerottensis, Webb, var. y. Orbignii ; major, umbilico paullo 

 largiore. 



Var. a agrees perfectly with six original Lanzarotan specimens 



