118 TEST ACE A ATLANTIC A. 



which arises out of a small granule or asperated point ; for, 

 although (like so many of the Helices) it has an occasional yel- 

 lowish-white albino state perfectly devoid of markings, its usual 

 aspect is a more or less banded one. "When the fasciae are 

 three in number, rather narrow, and well defined, the shell may 

 be said to be in its normal condition ; and under this aspect it 

 is generally to be met with throughout the greater portion of 

 Madeira proper and on the two southern Desertas. 



On the northern (or flat) Deserta, however, the H. vulgata 

 assumes a comparatively gigantic phasis ; the bands are broader 

 and more conspicuous (the third, or subsutural, one nenv-and- 

 then disappearing, or becoming merged into the second), and 

 the surface is more coarsely setose, — the setae (however small, 

 and fragile in their nature) being thick and remarkably visible. 

 This corresponds with my ' var. yS. deserticola ; ' and it is sin- 

 gular that it should have been confounded by Mr. Lowe (and 

 subsequently by Dr. Albers) with the ' var. 7. giramica^ of Ma- 

 deira proper, which has next to be considered. In reality it is 

 (on the average) a still larger shell than even the ' 7. giramica ;' 

 and it is also somewhat less depressed, less shining, much more 

 setose, and with the umbilicus less open, and its bands are 

 usually three in number, — being but seldom only two as in that 

 particular form. 



The two previous states may be described as trifasciated 

 ones ; but there are three others, worth placing upon record, 

 which are bifasciated. In the first of these (the ' 7. gira/mica' 

 of the present catalogue) the shell is large and rather depressed 

 (though perhaps not quite so large, on the average, as the ' 13. 

 deserticola ' from the Ilheo Chao), its surface is more shining 

 and bald, there being hardly any vestiges of minute bristles, its 

 umbilicus is appreciably wider, or more open, and its upper (or 

 subsutural) band is lost in the central one, the lower one also 

 being greatly increased in width. This conspicuously and 

 broadly bifasciated state is found for the most part about the 

 Cabo Ofiram, in the south-west of Madeira proper ; and it was 

 described, in 1852, as a distinct species, by Mr. Lowe, as the 

 H. giramica. 



The next state which merits notice is a smaller and (on the 

 average) more beautifully ornamented one than any of the pre- 

 ceding three, and I have generally met with it in the north of 

 Madeira proper, — as, for instance, near Sao Vicente, Seissal, 

 Ribeira da Janella, and Porto Moniz ; and it seems to corre- 

 spond with the ' var. pulchra ' of the Baron Paiva's Monograph 

 (mentioned as occurring around Sta. Anna), though he appears 

 to have confused or mixed it up with the very minute subfossil 

 aspect of the shell, with a reduced umbilicus, from the southern 



