ON THE BRITISH SPECIES OF SIMULIUM. 37 



densely clothed with, a similar pubescence to that of the thorax ; there is however 

 even in perfect specimens a narrow transverse bare band at the base of each segment. 

 Legs (fig. 3, d, front tarsus) as in the male, but sometimes with the femora and tibiae 

 much more extensively pale towards the base. Claws (fig. 2, e) much larger in 

 proportion to the size of the insect than in any other species of the genus ; they 

 are quite simple and not very much enlarged at the base ; as if to compensate for 

 the enlarged claws, the empodia are reduced in size. Halteres yellow. 



Time of appearmice. — Continuously from early March till September ; one specimen 

 in the British Museum was captured on 28th October. 



Distribution. — A common species in many districts in the South of England ; less 

 common in the north, and apparently unknown in Scotland. I have examined 

 specimens from the following localities : England : Padstow, Cornwall (L.) ; Taunton 

 (Miss B. K. Taylor) ; Wareham, Arne and Wimborne, Dorset (Y., M.), ; Christchurch, 

 Lymington and Brockenhurst, Hants. (J., K., L., V., Y.) ; Darenth, Kent (V .) ; 

 Oxshott, Surrey (H. Donisthorpe) ; Weybridge (F.) ; Felden and Bricket Wood, 

 Herts. (P.) ; Barton Mills, Suffolk (F.), Ampton, Barnham, Icklingham, Timworth 

 and West Stow, Suffolk (N.) ; Eynsham, Norfolk (F.) ; Oxford (H.) ; Attenborough, 

 Beeston, Clifton, Edwinstowe, Gotham, Radcliffe and West Leake, Notts. {Or., Y.) ; 

 Netheravon, Wilts. {Capt. E. P. Argyle) ; Wilton (J.) ; Grimshill, Salop. (L.) ; Burley 

 in Wharfedale (G.) ; Holmes Chapel, Cheshire {A. E. Cameron) ; Great Salkeld, 

 Cumberland {H. Britten). Wales : Llandrindod Wells {E. Brunetti). Ireland : 

 Killaloe, Co. Clare (M.) ; Cappoquin, Co. Waterford {K.). 



Habits. — This fly is a blood-sucker, and seems to have a partiality for horses. 

 Specimens were sent to the British Museum at different times by Colonel L. J. 

 Blenkinsop and Captain E. P. Argyle as having been taken on horses' ears. The 

 former observer wrote that " these flies are troubling horses here [near Salisbury and 

 near Christchurch] by sucking blood from their ears and causing ulceration." Outside 

 Britain its habits appear to be the same ; Captain C. E. P. Fowler has found it in 

 Morocco " swarming around gardens and marsh outside Fez ; attacks horses about 

 ears." S. hippovorum, Malloch, from Mexico, which is probably a near ally of this 

 species, has been recorded as having the same habit. S. equinum also attacks man ; 

 Mr. Hamm has observed that it bites quite severely. The females have more than 

 once been taken flying in company with those of S, ornatum (vide notes under the 

 latter species). 



Mr. H. Britten* has observed the oviposition of this species. He noticed the females 

 enter the water and deposit eggs actually on the submerged parts of plants. This 

 habit appears to be unusual, as it has not been recorded for any other species ; it 

 may possibly be correlated with the unusually large claws. 



Synonymy. — From the apparently definite connection of this species with horses, 

 I think it may be safely considered to be Linnaeus' Culex equinus, which has always 

 been assumed to be a species of Simuliuyn, while his short description corresponds 

 better with this species than with any other. Linnaeus simply describes the thorax 

 as black, with greyish sides (i.e. pleurae, presumably) ; as already mentioned, speci- 

 mens with a blackish mesonotum are not uncommon, and in these the three stripes 



*Ent. Mo. Mag., May, 1915. 



