378 TE!STACEA ATLANTIC A. 



Helix lancerottensis. 



Helix lancerottensis, W. et B.,Ann. des Sc. Kat. 33. syn. 12 

 (1833) 

 „ „ cVOrh. [nee diagn. p. 60], in W. et B. 



Hist. t. 1. f. 24, 25 (1839) 

 „ Orbignyi, var. calcarea, Mouss., Faun. Mai. des Can. 



37 (1872) 

 „ lancerottensis, Pfeiff, Mon. Hd. vii. 560 (1876) 

 var. Orbignyi . 



Helix Orbignyi (TF. et B.), dVrb., in W. et B. Hist. 59. t. 2, 

 f. 31-33 [nee coll. d'Orb] (1839) 

 „ „ et var. mitigata, Mouss., L c. 36, 37 (1872) 



var. adoptata. 



Helix adoptata, 3Iouss., I. c. 37. pi. 2. f. 39-41 (1872) 



Habitat ins. omnes Canarienses ; in inferioribus interme- 

 diisque, sub lapidibus, degens. 



Owing to the excessive carelessness of M. d'Orbigny, who 

 has altogether misunderstood and confused this common Ca- 

 narian shell, both Pfeiffer and Mousson seem to have been in a 

 hopeless state of doubt concerning it ; and no wonder, consider- 

 ing that d'Orbigny (in 1839) drew out his diagnosis of it from 

 a single bleached example of the H. monilifera, W. et B., 

 whilst the figures to which he refers, and which had been long 

 engraved under Webb's supervision and represent the species 

 which was published in the 'Synopsis' in 1833, apply to a 

 totally different shell, — coi'rectly depicting, in fact, the true 

 H. lancerottensis ! In reality the H. Orbignyi, W. et B., is 

 only a rather larger, thinner, and occasionally hispid form of 

 the lancerottensis, which obtains more particularly in the cen- 

 tral and western portions of the archipelago, — the smaller, more 

 calcareous, and glabrous one (the ' H. Orbignyi, var. calcarea ' 

 of Mousson), and which is Webb's type of his lancerottensis, 

 being especially characteristic of, though by no means peculiar 

 to, the two eastern, and much drier, islands of the Oroup.' 



The above is in complete accordance with the remarks of 

 Mr. Lowe in his paper on the shells observed at Mogador. Al- 

 luding to the surprising inaccuracy of M. d'Orbigny, he says : 



' The H. lancerottensis occurs also at Mogador, on the ojDposite coast of 

 Morocco (from whence I possess manj^ examples) ; and Mr. Lowe, in referring- 

 to this tj/pieal form of the shell, says (vide ' Journ. of the Linn. Soc' for 18G0, 

 p. 199), ' It agrees perfectly with six original Lanzarotan specimens sent to 

 me by Webb in 1829, of his If. lancerottensis, and with others found bj' myself 

 and Mr. Wollaston last year not only in Lanzarote and Fuerteventura, Init 

 also (together with the H. Orhignyi, Webb) in all the Canary Islands.' 

 These six original tjr|:)es are now in my own collection, and I can vouch for 

 the correctness of BIr. Lowe's conclusion. 



