94 



DIPTERA. 



were discovered by Mr. Fiohtel, who, lie adds, has thus established the habitat of this 

 singular creature beyond dispute. 



Linnaeus, to whom only an individual species of Diopsis was known, as usual with 

 him under such circumstances, does not assign to it any specific character. Donovan 

 states that he was acquainted with another species of this genus, a native of Africa, 

 in the collection of T. Marsham, Esq. which rendered a deviation from his example 

 excusable, although the latter was at the time undescribed. 



Since the preceding observations by Donovan was written, great additions have 

 been made to this curious genus. Fabricius, like Donovan, adopted the Linnaean 

 specific name ichneumonea, but confounded under that name two species distinct 

 from each other, and from the original species. Illiger added another species, D. 

 nigra. Dalmau described three new African species ; Weidemann another, which he 

 named in honour of Dalman ; and Gray another, D. Sykesii, in Griffith's Animal 

 Kingdom. More recently, in the seventeenth volume of the Transactions of the 

 Linngean Society, I have published a monograph upon the genus, in which I have 

 described thirty-one species, giving coloured figures of the greater portion. All of 

 these species, (with the exception of D. brevicornis of Say, which belongs to a dis- 

 tinct subgenus,) are natives of the old world, inhabiting Guinea, Sierra Leone, 

 Senegal, the Cape of Good Hope, Arabia, and the East Indies. 



In this monograph I have endeavoured to prove, that Guinea, or the adjacent 

 parts of "Western Africa, is the true locality of D. ichneumonia ; whilst Donovan's 

 species, which belongs to a distinct section of the genus with the spot on the wings 

 terminal, (and not merely a sub-apical fascia, as in D. ichneumonia,) I have given as 

 a distinct species, under the name of D. Indica. 



