86 BRITISH BLOOD-SUCKING FLIES BRACHYCERA—TABANIDAE 87
Oí the females can really be applied to either sex. The dilated first antennal
segment mtphed by the name " crasskomis " is not entirely reliable, for, as
Verrall (1909, p. 336) points out, the males oi pluvta/is may have a stouter
first antennal segment than the females of crassicornis ; but crassiconns may
always be recognised by the entirely shining first segment, and the entirely
black third segment of the antennae.
According to the specimens in the iMuseum collection, the size of this species
varies from 8-5 to io-6 mm. in the male, and 8 to 11-5 mm. in the female.
hile H. crass¿coniis is widely distributed in the British Isles, as also in
Continental Europe, it is, generally speaking, less common than H. phivialis
Aerrall ^1909, p. 331) and Goffe (1931, p. 64) both regard H. crassicornis as
commoner in Scotland than in England, and consider it likely to exceed in
numbers H.phwialis, at least locally. Mr. Goffe (in correspondence) writes :
" I have often been pestered by crassicornis in Scotland. On 24th June, 1933,
in Glenmore Forest they were very abundant. It goes to higher altitude!
pluvial is r Cameron, on the other hand (1934, p. 213) found crassicornis
comparatively rare in Scotland.
The dates of capture of the Museum specimens range from May 24th to
July 27th, while Verrall's records extended to August 14th.
It is remarkable that in the series of this species in the Museum the males
should outnumber the females—eighteen males to eleven females—especially
since the specimens were taken on a number of different occasions. This is
not an instance of the temporary and local occurrence of males only, such as
was noted above pluvialis, and it may perhaps indicate that thé females
of crassicornis are less prone to attack man than are those of the other species.
Local swarms of males do occur in crassicornis, as shown by a note by Aliss
Ricardo (1906, p. 98) : " The four males collected by me form part of a series
oí two dozen or so caught in one week, resting on the highest and sunniest
spots of a stone wall round an unoccupied farmyard. No females were to be
seen. I was not successful in discovering their breeding-place."
According to Krober (1922, p. 155) the area of distribution of H. crassicorfizs
includes Europe and Morocco.
Haematopota italica Meigen
So long ago as 1834 a very fair coloured figure of the female of this fly was
published by Curtis in his " British Entomology," but in spite of this the species
is only slightly better known in Britain than H. bigoti. Hitherto the species
does not seem to have been met with in Wales, Scotland or Ireland, and most
of the specimens so far collected, like those of Curtis, have been obtained in
Essex. Verrall and Yerbury found it not uncommon in the salt marshes of
the Essex and Suffolk coasts in 1907.
In the female sex H. italica is readily distinguishable from any other
British species of Haematopota by the length of its antennae (see key, p. 84).
The antennae of the 7nale, however, are not unusually elongate, and in'this sex
care is necessary to avoid confusing italica with pluvialis. The male of italica
presents the following differences when compared with the male of pluvialis.
The hair on the eye is much longer ; the fringe of erect hair on the hind margin
of the vertex is shorter, and yellowish or buff-yellow instead of black ; the first
segment of the antenna is clothed mainly with yellowish instead of black hair
(at least above) ; the pale markings on the dorsum of the body, including the
thoracic stripes and abdominal spots are much more distinct, and the wings
are paler.
This species is on the wing throughout August. There are specimens in
the Museum taken on 23rd July and 4th September, and Verrall (1909, p. 345)
says : " one female occurred at Aldeburgh as late as September 19th."
The size of specimens in the British Museum varies from 9 mm. to 10-5 mm.
in the male, and 10-4 mm. to 12-6 mm. in the female.
In this country italica is apparently coastal in distribution. Goffe (1932(5,
p. 42) suggests that the single record for Matley Bog, New Forest, may be
accounted for by specimens carried by wind from the Calshot area, where he
found the species, though sparingly, in 1931 and 1932. In Denmark, according
to Lundbeck (1907, p. 106) H. italica is as common s.'s, pluvialis, or nearly so,
and it often occurs together with this species.
Haematopota bigoti Gobert
This species, described in 1883, from material obtained in the Landes
district of south-western France, and apparently from the female only, is little
known in the British Isles, and is at present represented in the Museum collection
by fewer than a dozen specimens. All these are females, and are chiefly
from the south-eastern counties of England. The male has apparently not yet
been taken in this country.
The female rather resembles that of pluvialis, but the wing-markings in
fresh specimens (according to Goffe) are noticeably paler, while the middle
and hind femora are more or less yellowish. Usually they are grey or black
only at the tip, but sometimes the base, particularly of the middle femora is also
dark. When the wings are spread out the species is easily recognised by the
conspicuous pale spots on the first abdominal segment (female). The head is
also distinctly broader, when compared with a female of H. pluvialis.
Verrall (1909, p. 770) figures the eye-markings in this species, and states
that the bands appear to be different from those of the other British species of
Hae^natopota.
H. bigoti has so far been taken in this country only in July and August.
The eight females of this species in the Museum, from localities in Suffolk,
Essex and Kent, and from Studland, Dorset, bear out Goffe's conclusion that,
in this country at least, this species frequents coastal marshes. It has also been
taken in Somerset (Tickenham) by Mr. H. L. F. Audcent, in Norfolk (Burnham
Overy) by Mr. P. Freeman, in Hants by Mr. Goffe (1932^, p. 42), and in
the Isle of Wight (St. Helens Oyster Beds) by Mr. A. H. Hamm.
The Museum does not at present contain any Continental specimens of this
species, but from records given by Krober (1922, p. 161) it occurs in Italy,
Hungary, Algeria and Morocco, as well as in the north and south of France.