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R. S. BAGNALL 
(Phloeothripidae), and Thripidae, and two-, four- or five-segmented in 
the AeOlothripidae, whilst the maxillary palpus is also two-segmented 
in the Tubulifera, but in the Terebrantia it is either two- or three- 
segmented in the Thripidae , and three- to seven-segmented in the 
Aeolothripidae , and in this latter family is geniculate in form. It is 
only recently that the Aeolothripid genus, Orothrips Moulton, 1 having 
the labial palpi five-segmented, and the maxillary palpi seven-segmented, 
was founded by Mr. Dudley Moulton, necessitating an extension of the 
family characters as given by both Uzel and Hinds. 
The single-jointed maxillary and labial palpi of Urothrips (PL III. 
figs. 6, 7). is an important feature in that puzzling insect, and the 
oblique series of seta-pits near the base of the maxillary palpus is sug¬ 
gestive, possibly indicating that, in some ancestral forms, division had 
taken place at that point. 
Antennae. 
The antennæ of the known Tubulifera are almost invariably 
eight-segmented, having the segments cylindrical, and usually longer 
than broad. The intermediate segments are, as a rule, decidedly longer 
than broad, more or less claviform, and furnished with simple sense- 
cones, all the antennal joints having a greater or less number of spines 
or hairs. 
There are, however two known Tubuliferous. genera, each with 
but a single species, in which the antennæ are only seven-segmented. 
They are Kladothrips Froggatt, 2 and Allothrips Hood, 3 but, with the 
exception or the number of joints, there is, in each case, no departure 
from, or modification of the type of antenna common to the Phloethri- 
pidae, and it is obvious that this reduction in the number of antennal 
joints is the result of the fusion, or union, of the two apical ones. The 
genus Neothrips Hood (closely allied to Allothrips) is an interesting- 
connecting link, having the two apical joints apparently connate, but 
with the separating suture still visible. 
It will at once be seen that the seven-segmented antennæ of 
Urothrips is of quite a different and distinctive type. 
1 A contribution to our Knowledge of the Thysanoptera of California. (U. S. 
Department of Agriculture, Bureau of Entomology. Technical Series, No. 12, 
Part III., I—VI., pp. 39—68., plates I— VI., April 5th 1907.) 
2 Australian Insects. Sydney 1907. p. 394. tab. 37, fig. 3—5. 
3 New Genera and Species of Illinois Thysanoptera. (Bulletin of the Illinois 
State Laboratory of Natural History, VIII., Art. II., pp. 361—379., figs. 1—9. 
Aug. 22. 1908.) 
