DISTRIBUTION OF INSECTS. 



281 



expect to be amongst the first to reach and colonize so isolated a 

 spot as St. Helena. 



The few insects of other orders known to me as natives of St. 

 Helena are quite of the same stamp as the Lepidoptera as to 

 likelihood of their having been introduced. The brilliant Sphex, 

 Chlorion compressum, which I noticed on the walls in James 

 Town, is a well-known native of India and Ceylon, and doubtless 

 "came over" with its particular favourites, the cockroaches. 

 Gryllus capensis, again (a St. -Helena specimen of which, in the 

 British Museum, is recorded in the official ' Catalogue of Der- 

 maptera Saltatoria,' pt. i. p. 16), is a cricket of world-wide dis- 

 tribution, being known to occur in Southern Europe, Western 

 and Eastern Asia, every quarter of Africa, North and South 

 America, Australia, the Philippine Islands, Borneo, and Mau- 

 ritius. 



As regards the Coleoptera of the island, I am not in a position 

 to speak from personal observation ; but it is clear, from Mr. 

 Murray's own remarks and those which he quotes from Mr. Wol- 

 laston (pp. 22-24), that a very considerable proportion of the 

 species may safely be regarded as introductions from other 

 countries. 



While touching on the subject of dispersal, I wish to observe 

 that the frequent occurrence of insects out at sea, very far from 

 land, scarcely receives the attention which it deserves, and that 

 my own slight experience assures me that a careful record of 

 instances of the kind would prove very instructive and valuable. 

 In the journal of a voyage, made in the year 1858, from England 

 to the Cape, I noted the various insects that made their appear- 

 ance on board the ship in which I sailed. They were as follows 

 (I add the date and approximate distance from the nearest land # 

 in each case), viz. : — 



1. Byrameis Cardai. May 28th. About 90 miles west of Te- 

 neriffe. 



2. A pale-yellow Moth, apparently a Bombyx, about the size of 

 the Silkworm Moth (B. Mori). Same date and position. 



3. Botys sp. ignot. June 5th. About 230 miles from the 

 mouth of the river Gambia. 



4. A small Longicorn Beetle {gen. ignot.). June 6th. About 

 230 miles from the mouth of the river Jeba. 



* The distance is roughly calculated from the recorded position of the ship 

 at noon on each of the days mentioned. 



