COOKE: DISTEIBUTIOX AND HABITS OF ALOPIA. 91 



On the main chain of the South Carpathians the range of the 

 group is sluirply detined. It is not found west of the Konigstein, 

 or east of the village of Bodza-vama, at the foot of the Cznkas and 

 the Dobromir. In other words, it inhabits about 65 to 70 km. only 

 of the main chain. The highest peaks of the range stretch unbroken 

 westward of the Konigstein, but at the Konigstein Alopia stops dead, 

 to appear once more, in a single species and two varieties, 150 km. 

 to the west, near the Szurduk Pass into Koumania. 



2. Locality. — Within these limits Alopia occurs exclusively in the 

 Jurassic, Cretaceous, and Eocene limestones. It is essentially a rock- 

 haunting group ; in vain will you look for it on trees, or on mossy 

 banks, or amongst nettle-roots, or under stones, or in any of the 

 localities affected by the ordinary British or Continental Clausilia. 

 The open mountain ridges, the perpendicular cliffs, the huge boulders 

 which have become detached from the precipices, are its chosen home, 

 and it occurs nowhere else. Quite exceptionally I have found 

 a few specimens of Meschendorferi, Bielz, on tree trunks growing close 

 to great boulders, but this was under circumstances which made it 

 crawl about in a state of excitement, and plumbea, Ilossm., may be 

 found on old walls in Kronstadt itself. But one soon learns the 

 lesson that it is waste of time to look for Alopia on any mountain 

 within the favoured area, unless that mountain contains bare faces 

 of limestone cliff; if these occur, it may be predicted with f^onie 

 certainty that Alo^n'a will be present also. 



The great limestone range of the South Carpathians is cut into 

 deep and precipitous valleys. These ' Schluchten ', the sides of which 

 often rise in cliffs 500 to 1,000 feet high, and are sometimes so narrow 

 that you can almost touch both sides with outstretched arms, are 

 invariably tenanted by Alopia, and the same species will often vary 

 considerably, e.g. in the upper and lower ends of the same ' Schlucht'. 

 How variable the group is, is shown by the fact that Kimakowicz 

 only recognizes fourteen species and sub-species, while he enumerates 

 fifty-eight named varieties. 



It is remarkable within what narrow limits a species or a definite 

 variety will occur. I will give some instances of this. Bielz ' 

 describes A. Meschendorferi a,?, occurring exclusively on the Zeidnerbeig, 

 a somewhat isolated mountain about seven miles from Brasso. In 1909 

 I went up the Zeidnerberg with the object of collecting this species. 

 On the ascent I searched for it in every possible locality without 

 any success. I arrived within two minutes of the top without having 

 secured a single specimen, and seriouslj' thought I must have climbed 

 the wrong mountain. Suddenly, on a low piece of exposed rock face, 

 the species appeared in abundance, and it is no exaggeration to say 

 tliat, for the remaining 50 feet, if I had wanted a thousand living 

 specimens, I could easily have taken them. 



The Great and Little Konigstein are separated by a narrow and 

 steep Schlucht called the Krepatura. On the perpendicular sides of 

 the Schlucht A. Fussiana, Bielz, var. insignis, a sinistral form with 



' Fauna der Land- und Silsswasscr-Molhiskcn Sicbcnbfnrjcns, p. 127. 



