A REVISION OF THE TSETSE-FLIES (GLOSSINA) BASED ON 
A STUDY OF THE MALE GENITAL ARMATURE. 
3y ROBERT NEWSTEAD, M.Sc., A.L.S., &e. 
The School of Tropical Medicine, the University, Liverpool. 
The examination of the armature of the males of all the hitherto described 
species of the genus Glossina, with the exception of G. maculata, Newstead,* 
has not only revealed some very striking morphological characters, but has led 
to the discovery of three new speciest and the re-establishment of Bigot’s 
G. grossa.t One of these new species, G. submorsitans, Newstead, has 
hitherto been overlooked through its striking similarity to G. morsitans. 
Morphologically these two species are separable chiefly by the small but 
important organs herein described as the median lobes ; these characters will be 
best understood by reference to the accompanying figures (figs. 1im/, 16m), 
in which the difference is as well marked as that between the holoptic and 
dichoptic heads found in certain groups of Diptera. G. palpalis, R. D., and G. tach- 
inoides, W estw., are also very closely allied in the general form of the armature of 
the males, but they are easily separable by the minute differential characters 
of the inferior claspers (figs. 9’, 117c). 
The scheme of classification here adopted for the members of this small, but 
very highly specialised genus, is, | believe, contrary to nearly every precedent, 
in so far as it begins with the lower and rises to the higher or more complex 
forms. It is based entirely upon the taxonomic characters of the armature of the 
males, which afford a natural and reliable guide for discriminating the superficially 
similar species, and indicate very clearly the alliances and distinctions which exist 
among these insects. That the species fall into three very striking and distinct 
groups may be easily gathered from a study of the illustrations accompanying this 
memoir, each group being distinguished by very trenchant characters. These 
are :— 
Group I—The Fusca Group. 
This division includes the four largest species of the genus: G. fusca, Walk., 
G. nigrofusca, Newst., and G. tabaniformis, Westw., which have a western distri- 
bution ; G. longipenn’s, Corti, and G. brevipalpis, Newst., occurring chiefly on the 
eastern side of the continent. In all of these species the superior claspers are quite 
free, there being no membrane stretching between them ; the distal extremities of 
these appendages have either a single large and bluntly-pointed tooth-like exten- 
sion, or they are bluntly bidentate ; the harpes in all cases being markedly 
different in structure. 
The only example known is unfortunately a female. 
Ann, Trop. Med. and Parasit., vol. iv., pp. 369-375 (1910). 
[After a careful re-examination of the types, Mr. E. E. Austen agrees with Mr. Newstead in 
regarding G’. gross, Big., as distinct from G. fusca, Walk., but he considers it conspecific with 
the earlier G'. tubaniformis, Westw., which name will stand. Myr. Austen is further of opinion 
that the species provisionally referred to G. grossa by Mr. Newstead is not the same as Bigot’s 
insect, and must therefore be known as G. nigrofusca, Newst., the name tentatively suggested 
for it by Mr. Newstead (/.c. p. 370).—Ep. ] 
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