AZOREAN GROUP. 23 



H. servilis and Lowe's pusilla are conspecific, he would not 

 have fallen into the error of supposing that the species had not 

 yet been observed in the Madeiran Group. But, so far from the 

 latter being the case, it was absolutely yi9's^ described (in 1831) 

 from Madeira, whei'e it is one of the most abundant of the 

 land-shells. 



The P. pusilla (assuming Morelet's identification of it to be 

 correct) appears to have been noticed hitherto only near Ponta 

 Delgada in S. Miguel, and in Fayal ; in the latter of which 

 islands it is expressly stated by Morelet to have been found in 

 rocky places near the sea. This exactly accords with its usual 

 habitat in the Madeiran archipelago, for it is comparatively 

 seldom that it is to be met with (like the P. placida, Shuttl.) in 

 the laurel-woods of a high altitude ; nevertheless it does occa- 

 sionally occur in the latter also, and therefore Drouet's remark 

 that, in Fayal, it exists ' au milieu des feuilles mortes dans les 

 bois de lauriers et de genevriers ' may be likewise applicable, — 

 for he would doubtless have at once perceived the difference 

 had the examples to which he alludes been referable to the 

 placida, rather than to the pusilla. 



Apart from its diminutive size, the P. pusilla (which is a 

 trifle smaller, darker, and more depressed than the placida) 

 may be readily known by a certain number of its oblique, 

 transverse, thread-like strise being more developed than the 

 rest ; for although they are sometimes exceedingly faint, at 

 others they are quite conspicuous and at once distinguishable 

 beneath even an ordinary lens. Morelet's figure, though other- 

 wise good, does not represent this latter character with suffi- 

 cient precision. 



Patula aculeata. 



Helix aculeata, MillL, Verm. Hist ii. 81 (1774) 

 „ „ Gratj, Man. 149. t. 4. f. 33 (1840) 



„ „ PfeijJF.,Mon.Hel.i. 50 {184.8) 



„ „ Morel., Hist. Nat. des Acor. 175 (1860) 



„ „ Drouet, Faun. Agor. 157 (1861) 



Habitat S. Miguel, et Fayal ; in montibus parce lecta. 



The European P. aculeata is recorded both by Morelet and 

 Drouet from S. Miguel and Fayal, where it appears to occur at 

 a rather high elevation ; but it has not hitherto been noticed 

 in any of the more southern archipelagos. According to Drouet 

 it is found in the laurel woods, amongst fallen leaves. 



