288 Fioceeili.iirjs of the Royal Irisli Acatlcmi/. 



Insects. 



The insects of the Atlantic Islands agree i^erfectly with all the 

 other cLisses of animals, in so far as they exliibit mostly South- 

 European or IS'oitli-Afriean affinities. Taking the various orders 

 separately, the Hymenoptera — or at any rate that gronp of Hymenoptera 

 to which the ants belong, have been fairly well investigated and are 

 of particular interest from a distributional point of view. 



A very minute ant {^Monomorium minutum cariotiarium) inhabits 

 ITadeira and also the ^est Indies and Central America ; but there is a 

 possibility of its having been introduced into the fonner locality by 

 man. The genus, as a whole, has a very wide range in the Tropics. 

 There is no other feature which might indicate a direct land-union 

 hetween ^Madeira or the Azores and America ; but Tenei-iffe is inhabited 

 by an ant {Lepiothorax gracilicornis) which is peculiar to it, and lias 

 some allied species in America, though most members of the genus 

 are Palfearctic. 



In the ^rediterr;inean region, we find a minute ant in decaying 

 wood (Epitn'tm argiolm). Xo other species of the genus has hitherto 

 been detect<'d in the Holarctic region ; in the TTest Indies, however 

 (Island of St. Thomas), another species has been met witli {SJ. 

 emmoi). 



Special attention is directed by Dr. von Ihering to the family 

 Dorylidse, which are principally African, a few species penetrating 

 into the Oriental and southern Palsearctic regions. A single genus 

 {JEciton) of this family is altogether confined to South America ; and 

 being closely allied to the African genus Anomma, its distribution 

 contributes additional evidence, according to von Ihering, in favour of 

 the tluoiy that these two continents have formerly been connected 

 with one another (D, p. 418). 



Our knowledge of the distribution of flies is still very incomplete. 

 Dr. Dahl, who has collected them in the Azores, maintains that they 

 are there thorougtly European in character (p. 333) ; and there is 

 apparently nothing else which calls for special notice. 



The lepidopterous fauna of the Atlantic Islands has been carefully 

 studied by quite a number of competent observers. Eebel and Rogen- 

 hofer give us an excellent accormt of the species inhabiting the Canary 

 Islands ; and they inform us that the whole lepidopterous fauna of the 

 archipelago has probably undergone profound modification, owing to 

 the almost complete destruction of the native forests duiing the last 

 few centuries. Still there are 183 species left. Of these, sixty-one 

 occiu- also in Madeira. The Canaries possess 70 per cent, of their 



