WINGLESS REPRODUCTIVE TYPE OF TERMITES 617 
The second form of P. simplex 
The second form of P. simplex has so far been found in Florida 
only in the nearly mature nymphal phase, and is not present in 
any phase in the Cuban or Jamaican material of this species. 
These nymphs (fig. 15) may be recognized by their peculiar wing 
pads, or vestigial wings, which differ greatly from those of the 
second type of other termites. The body length is 5.5 mm., 
less than that of the first-form adult, but slightly larger than 
either third-form nymphs or workers. The head is broader than 
that of the first-form adult, but the compound eyes are much 
smaller and less bulging. The abdomen is stouter than in 
either third-form nymph or worker. The body color both in 
life and after fixation is an opaque creamy white. 
‘The number of antennal segments is quite constantly eighteen. 
The most characteristic features of the external anatomy are the 
fused wing pads (figs. 15, 19, 20), appearing as shield-shaped and 
partly transparent structures projecting beyond each lateral 
margin of the thorax and also in a posterior direction. The 
right and left wing pads of each segment are fused in the median 
line, and do not extend backward as in the normal type. The 
wing pads of the mesothoracic segment are larger than the meta- 
thoracic, and the venation differs slightly in the two. The same 
veins are present as in the wing of the first form, although the 
subcosta (figs. 19, 20, sc) is in a less developed stage, appearing 
in both wing pads merely as a thickened marginal area, except 
at the base of the hind wing where a true vein begins but shortly 
ends in the thickened margin. As in the first-form adult wing, 
a ‘radial sector’ (r 4 + 5) is present in the hind wing only. 
Internal anatomy. The brain is more highly developed in the 
second-form nymph than in any of the other castes except the 
first form. The mushroom bodies and optic lobes are very 
large, and correlated with the size of the latter are the large 
Fig.15 Prorhinotermes simplex. Nymph of second form, female, drawn from 
a whole mount. 
Fig. 16 Prorhinotermes simplex. Nymph of third form, female, drawn from 
a whole mount. br, brain; f.g, frontal gland; ov, ovary; s.g, salivary gland; v, 
vestige of wing. Leitz oc. 4, obj. 1, table level, reduced one-third. 
