CUKCULIONID^. 271 



affirm my belief that the difficulties gradually diminish, in propor- 

 tion as we become acquainted with the objects themselves which we 

 would endeavour to describe ; for when viewed superficially, nothing 

 can be more plausible than the easy and wholesale conclusion that 

 all of them alike are but chance developments from a central type. 

 Even as regards the obscurer forms, however, there is yet one way 

 (whensoever a favourable opportunity may occur for practising it) by 

 which we may hope to arrive at a considerable amount of truth, 

 namely, by a careful inquiry, into their previous states and modes of 

 life. The good results of such an investigation have been more than 

 verified by the late researches of the Messrs. Crotch, who took the 

 pains not only to collect but also to note the particular plants on 

 which the species which they happened to fall in with subsist ; the 

 consequence of which has been that at least three or four forms, the 

 distinctions between which (from the want of proper material) I 

 had looked upon with some suspicion when compiling my Canarian 

 Catalogue, have been so fully established that there can be no longer 

 any doubt as to their true specific claims. Such, for instance, are 

 the A. argillosus (which is peculiar to the Kleinia neriifolid), the 

 ceonii (to the Semperviva), the fortunatus (to the EuphorHce), and 

 the senilis (to the fig). 



With these few remarks therefore I would commend the numerous 

 Acalles recorded in this Catalogue to the patient observation of those 

 who may have opportunities, from time to time, of testing their 

 diagnoses, and (if needs be) of correcting them merely adding that, 

 although I feel it anything but improbable that some few may 

 eventually have to be suppressed, I nevertheless believe that by far 

 the greater number will stand the test of a rigid inquiry, and that a 

 careful attention to the exact plants on which they severally feed 

 will further tend to elucidate those particular forms which the defi- 

 ciency of material has compelled me to leave in partial doubt. 



751. Acalles Neptunus. 



Acalles Neptunus, WolL, Ins. Mad. 330 (note) (1854). 

 , Id., Journ. of Ent. 90 (1860). 



Habitat Salvages (ins. minorem, australem), a Dom. Leacock tempore 

 vernali A.D. 1851 deprehensus. 



This noble Acalles appears to be peculiar to the Salvages, where 

 several specimens of it were captured by Mr. Leacock of Madeira 

 on the Southern island (or e Great Piton ') during the spring of 



