96 BRITISH BLOOD-SL'CKING FLIES
the rest was never a preliminary to a dip. . . ." Goffe, however (1935, p. 107),
comes " to the conclusion that the very few males which have hitherto been
referred to solstitmh's Meig. belonged either to tropicus Linn., sensu Collin
or to some other allied species, and that we have not previously recognised thè
male of solstifialis Meig." This author records the capture of ten males which
he believes to represent the true solstifialis Meigen, of which " eight were
drinking and had a habit quite similar to that of Ss. paganns [=T. bisignatus
Jaenn.]." These males closely resemble the males of bisignatus, and Goffe
gives a table of differences between them.
Lundbeck (1907, pp. 120-121\ writing oi solstitialis in Denmark, states
A a t the pupa measures from 18 to 20 mm. in length, and that a larva found by
him on May 22nd, pupated on June 1st, the imago making its appearance
fifteen days later. Another larva found in July spent eleven days in the pupal
state. " The larvae were very voracious, one devoured twelve lar^•ae of
Hoplodonta vindula [Stratiomyiidae] in a few davs. Brauer states that the
pupa is found in water. I do not think this is correct, my larvae would not
transform in the water, but when I put the full grown larvae in earth they soon
transformed. A larva which I kept in captivity for some time, but without
feeding it, transformed at last to pupa, but this was small and the imago only
measured 12-5 mm."
The species is found over most of Europe, Siberia and Asia Alinor. " There
is no sure record of it from Scandinavia " (Lundbeck).
Tabanus tropicus Linnaeus
(Fig. 3>)
Goffe (1931, p. 94^ and Collin (1932, p. 39) have suggested that the females
of this species should have lateral orange patches on three segments of the
abdomen, while in the male these markings should extend to the fourth segment.
This definition excludes most of the specimens hitherto recorded by
various authors as T. tropicus,
y j j f f i which are now regarded as
being merely lighter specimens
of T. bisignatus Jaenn. (see p.
92). An exception is the record
of Duncan (1840, p. 328), who,
figuring a male, distinctly states
that the first four segments are
widely fulvous at the sides. He
adds : " This species is not one
of the most common, but it
occurs now and then throughout
the country . . . eyes
green, with three transverse
rays of purple."
FIG. 31.—R. tropicus Linn. Head.
A s thus restricted the species includes only one of the specimens listed by
\ errall (1909, p. 360), the female from Worcester, July 3rd, 1869, which
\ errali (previous page) mentions as having been accepted as tropicus by the
BRACHYCERA—TABANIDAE
Continental worker, Brauer. In the addenda (p. 771) Verrall mentions thirtyeight
females taken by Colonel Yerbury at Crymlyn Bog, Glamorgan on July
24th, 1908, which Collin (1932, p. 39) accepts as conspecific with the Worcester
specimen. Collin also states that he has found this species early in August in
the Norfolk Broads. The British Museum possesses eleven of the Crymlyn
Bog specimens and two females of this species taken in the Norfolk Broads by
Professor P. A. Buxton. There are also two females from Kenmare, County
Kerry, and Glengariff, County Cork.
T. tropicus Linn, as thus limited is very difficult to separate from T. solstitialis
Meigen (see key). There are apparently few reliable records of males
of this species from Britain, all the published records, including that of Jones
(1922, p. 41) referring to the light form of bisignatus Jaenn, but Mr. Goffe
informs me that Mr. Collin found the males as numerous as the females at
Horning in July, 1934.
According to the specimens available in the Museum collection this species
has been taken between June 13th (Cork) and August loth (Norfolk), and
always from a locality on or near the coast. Krober (193S, p- 72) gives its
occurrence as May to August, and its distribution as Europe, Siberia, Japan
and Formosa.
Stammer, who has collected and studied Tabanid larvae in the vicinity of
Greifswald in north Germany writes (1924, p. 123) : " Of the species of Tabanus
the larva of Tabanus tropicus . . . was the most common, I found it almost
always in the damp moss of marshy meadows, in the mossy margins of forest
pools, or in fields. On a few occasions I also met with it in the mud, much
mixed with leaves, of a nearly dried-up pool in W^ampen Forest." On a
subsequent page (p. 132) Stammer gives a description of the larva, which he
says may attain a length of 30 mm. ; the pseudopods and striation are strongly
developed ; the ground colour is brownish, and there are two longitudinal
rows of darker spots on the outer side of the dorsal pseudopods on the first to
eleventh segments. Unfortunately it is not clear whether the species referred
to is T. tropicus in the present sense, or the light form of T. bisignatus
{T. pagajius Fabr. according to Goffe.)
Tabanus plebeius Fallén
(Fig- 32)
Although the forecast of Verrall (1909, p. 381) that this species " will
probably occur in Britain, as it has been found in France and Denmark " was
justified two and a half years later, the three specimens in the Museum are the
only British specimens known to me.
T. plebeius is the smallest British Taba7ius, measuring only 10-5 to 11 mm.
in length. It is a dusky mouse-grey species, clothed with short greyish or
yellowish-grey hair, and, in the female sex at least, with a double longitudinal
series of triangular black marks in the centre of the dorsal surface of the
abdomen. From T. rusticus, with which alone it is likely to be confused,
plebeius may be distinguished by its smaller size, and by the greater length,
particularly in the male, of the fringe of erect hair on the upper portion
7