1913.] 107 



THE IDENTITY OF CULEX GENICULATUS, Olivier. 



BY F. W. EDWARDS, B.A., F.E.S. 



(Published by })ermission of the Trustees of the British Miiseiun.) 



Culex geniculafus was described by Olivier in 1791 (Eiicycl. 

 Method., vi, p. 134) in the followinp; terms : — 



" Culex thorace cinereo nigro lineato, pedibus fuscis, geiiiculis albis. 



" II est de la graiideiir da Cousin comraun. Les antennes sont obsciires. 

 La trompe est noire, un peu phis longvie que la moitie dn coi-ps. La tete est 

 cendree. Le corcelet est cendre, avec deux lignes longitudinales noiratres, 

 presque reunis, au milieu du dos, et une autre courte de chaque cote. L'abdo- 

 men est obscur, avec le bord des anneaux blanchatre. Les pattes sont noiratres 

 avec la base des cuisses et le genoix l^lancs. Les ailes sont transparentes avec 

 les nervures et le bord interieur cilies. 



" II se trouve aux envii'ons de Paris, dans les endroits humides." 



In 1827, Kobinean-Desvoidy mentioned the species in his Essay 

 on the Cvlicidx ; he had not met with it himself, but he translated 

 Olivier' s description into Latin. It is worth noting that he placed it 

 next to Culex, lateralis, Mg., of which he also gave a Latin diagnosis. 



After this no mention of the species under Olivier 's name occurs 

 in Entomological literature until 1896, when Ficalbi dealt with it 

 (Bull. Soc. Ent. Ital., xxviii, p. 292), including it with his C. liortensis 

 in that division of the genus Culex, having the abdomen dorsally 

 banded, the light band coming behind the dark on each segment. 

 Why he placed it in this position is far from clear, but by so doing 

 he apparently led Blanchard (Les Moustiques, 1905, p. 367) to sink 

 C. liortensis as a synonym of C. (leniculatus. 



The object of the present note is to suggest that there is no 

 connection between C. geniculafus and C. hortensis, but that C. geni- 

 culatits is really the species which was subsequently described by 

 Meigen as C lateralis (Syst. Beschr. i, p. 5, 1818). It will be noticed 

 that Olivier, in describing the abdomen, says it is " obscur, avec le 

 bord [not le bord posterieur] des anneaux blanchatre." In this sen- 

 tence the impression given is distinctly that the lateral rather than the 

 apical portion of each segment is whitish, at least the words will 

 easily bear this interpretation. Now there are but two North 

 European gnats having an abdomen coloured thus, Aedes cinereus 

 and OcMerotatus lateralis. The former need not be considered as 

 Olivier's description of the thorax of his insect will not apply to it. 

 0. lateralis, however, answers perfectly to the description ; specimens 



