1963] 
Carpenter — Carboniferous Insects 
125 
slightly in the origin of MA. As pointed out above, in both the foie 
wings the proximal part of MA is close to the proximal part of Rs and 
in the left fore wing MA can clearly be seen joining to R. In the hind 
wings, on the other hand, MA is quite remote from Rs proximally and 
in the left hind wing it appears to join MP very close to the stem of 
R. These differences were recorded by Brongniart not only in his 
figure (18-9) but in his description of the fossil, in which he states 
that although this vein in the anterior wing arises from the radius, in 
the posterior wing it arises from the very base of the wing. However, 
in his restoration of pulchella (fig. 14, p. 327), he does not show MA 
joining R in the fore wing although he does represent MA as being 
closer to R and Rs in the fore wing than in the hind wing. Hana- 
lirsch’s figure (see fig. b, plate 13) of Triplosoba was taken from 
Brongniart’s restoration in figure 14 rather than from his drawing of 
the fossil itself on plate 18; in the process Handlirsch apparently 
missed the difference between the fore and hind wings with respect 
to the origin of MA and its relationship to R and Rs. Similarly, 
Tillyard’s drawing of a Triplosoba wing, adapted from Handlirsch, 
shows more nearly the condition of the hind wing but with the stem 
of M more remote from R than actually is the case. Demoulin’s 
figure of the wing misses completely the difference in the position of 
MA with respect to Rs in the fore and hind wings ; in fact, in his hind 
wing he shows MA actually closer to the base of Rs than it is repre- 
sented in the fore wing. 
Body. The body structure of Triplosoba is only vaguely preserved 
in the fossil. There is a suggestion of a head (which is interpreted by 
Demoulin as the prothorax), thorax and abdomen; three legs are 
indicated in the fossil, all of these being on the right side of the insect 
as preserved in counterpart 18-9. The segmentation of the legs is not 
clear and Demoulin’s conclusion that the tarsi were five-segmented is 
unjustified. There is no question, however, as mentioned by Lameere 
(1917) that there are three caudal processes, the two cerci and the 
median filament. As shown in Brongniart’s figure of 18-8 as well as 
in his restoration, figure 14, the median filament is much longer as 
preserved than it is in the cerci ; this could of course be the result of 
the incomplete preservation of the latter. Demoulin has described and 
figured what he considers to be a gonostyle but actually the structure 
concerned is not part of the fossil ; it is due entirely to an irregularity 
Explanation of Plate 13 
Triplosoba pulchella (Brongniart). a) restoration of Demoulin; b) restor- 
ation of Handlirsch; c) Brongniart’s figure of counterpart 18 - 8 . For further 
explanation see text. 
