200 INDEX. 



Helix commixta, Lowe, sedentary nature of, 132. 

 coronata, Desh., its peculiarity to Porto Santo, 128 ; its occur- 

 rence beneath the surface of the ground, 131. 



coronula, Lowe, its peculiarity to the Southern Dezerta, 128. 



Delphinula, Lowe, the Madeiran representative of H. tectifor- 



mis in Porto Santo, 129. 



discina, Lowe, a form of H. polymorpha, 133. 



erubescens, Lowe, its powers of diffusion greater than those of 



its allies, 133; sensitive to external influences, 134. 



fluctuosa, Lowe, its extinction in Porto Santo, 131. 



hirsuta, Say, two distinct states of, 106. 



lapicida, Linn., its extinction in Porto Santo, 131. 



latens, Lowe, the Madeiran representative of H. obtecta in 



Porto Santo, 129. 

 lincta, Lowe, the common Madeiran form of H. polymorpha, 



134. 



Lowei, Pfr., perhaps a gigantic state of H. Portosanctana, 106. 



papilio, Lowe, a form of H. polymorpha, 133. 



paupercula, Lowe, its powers of diffusion greater than those 



of its allies, 133. 

 polymorpha, Lowe, sensitive to external influences, and of 



great diffusive powers, 133. 



Portosanctana, Sow., its peculiarity to Porto Santo, 129. 



pulvinata, Lowe, a form of H. polymorpha, 133. 



saccharata, Lowe, a local state of H. polymorpha, 134. 



senilis, Lowe, the Dezertan form of H. polymorpha, 134. 



squalida, Lowe, the Madeiran representative of H. depauperata 



in Porto Santo, 129. 



tiarella, Webb, its sedentary nature, 128. 



undata, Lowe, its peculiarity to Madeira proper, 129. 



Vulcania, Lowe, its peculiarity to the Dezertas, 129. 



Wollastoni, Lowe, sedentary nature of, 132. 



Helobia nivalis, Payk., perhaps a state of H. brevicollis, 40. 

 Helops, always apterous in Madeira, 82. 



confertus, Woll., varies from altitude, 39. 



futilis, Woll., varies from isolation, 109. 



testaceus, Kiist., pallid hue of, 64. 



Vulcanus, Woll., large size of, on one of the Madeira Islands, 88. 



Henfrey, Prof., on disturbing agents, 8. 



Herschel, Sir John, on the requisites for an observer, 12. 



Hipparchia Semele, Linn., has a distinct aspect in Madeira, 34. 



Hipporhinus, its concentration in S. Africa, 143. 



Holme, Mr., on Olisthopus rotundatus in the Scilly Islands, 58, 102 ; 



on a winged state of Phosphuga atrata, 102. 

 Holoparamecus, common to Madeira and Sicily, 139. 

 niger, Aube, different in Madeira and Sicily, 33. 



