WHEELER— ANT LARV.^. 317 



contrary, in the part of the abdomen which is easiest accessible to the termites, 

 viz., the ventral, lateral and posterior side of the pseudoabdomen, 



1. The fat-body is not surrounded by the blood-tissue but contiguous 

 with the extremely thin hypodermis and 



2. The cuticle is penetrated by an immense number of pores (and the 

 endostracum is not distinctly discernible). 



3. Furthermore Termitomimus does occur in great numbers in the nests 

 of the termites. 



These facts seem to me to suggest that in Termitomimus the fat itself 

 or a derivate of the fat-body may possibly be secreted as a fluid through 

 the numerous pores of the cuticle and not m.erely evaporate and that Ter- 

 mitomimus thus offers to the termites a source of subsistence. The com- 

 paratively very large extension of the area of the cuticle which exhibits this 

 structure also argues in favor of this theory. 



In another paper (1907a) Tragardh describes a peculiar Tineid 

 caterpillar with exudatoria even more like those of the PacJiysima 

 larva. He found it in the tree nests of Rhinotcrmcs in Zululand. 

 The relations between the caterpillar, which feeds on the woody sub- 

 stance of the nest, and the termites are evidently friendly. 



When disturbed, the larvse were seen to make their way to other parts 

 of the nest, coming along one after the other, with regular intervals, like in 

 a procession, each larva being escorted by a few soldiers and workers. 



Each of the seven anterior abdominal segments of the caterpillar 

 bears on its sides a pair of long, tapering appendages, which 

 Tragardh regards as exudatoria and each appendage contains a lobe 

 of the fat-body, surrounded by blood. The imperforate hypodermis 

 is separated from the thin cuticle, the space between being filled 

 with exudate. In this case he believes that the exudate must evap- 

 orate on the surface of the body, since he says : 



As the larva emits a strong odor, and the termites were scarcely seen 

 touching the appendages, the exudation is very likely an alluring odor. 



He compares the organs with the various osmateria described by 

 Packard in the caterpillars of Megalopygc and Hemileucidae. 



Certain organs in the larvae of two groups of Hymenoptera may 

 also be interpreted as exudatoria. In 1907 I called attention to 

 peculiar blister-like organs on the sides of pseudonymphs of certain 

 Eucharine parasites of ants, notably in Oraseina. These structures 

 are shown in Figs. 19 and 21, PI. 2 of the paper referred to and in 

 Fig. 251 F, G, p. 415 of n-\y ant book (1910). In the pupa of the 



