352 ERNEST WARREN. 



gland Avitli a i-eceptacle ; it is similar in sti-ucture to a pair of 

 dorsal hypodermal glands in the imago, which, however, are 

 situated in a different segment of the abdomen. 



(12) In the larva the abdominal nerve-chain contains 8 

 pairs of ganglia, but there is a distinct concentration of the 

 ganglia, and the whole chain is contracted forwards, so that the 

 8th pair lie in between the 5th and 6th abdominal segments 

 instead of in the 8th segment. In the imago the abdominal 

 nerve-chain is reduced to an elongated mass, consisting of 

 7 or 8 united ganglia, which has fused on to the metathoracic 

 ganglion. 



(13) In the larva there is a postoral commissure im- 

 mediately behind the oesophagus. This is regarded as the 

 commissure of the mandibular ganglia. In the imago the 

 structure is entirely incorporated in the suboesophageal 

 ganglion. 



(14) Abdominal spiracles are dorsally placed in both. 



It may be noticed that all the more important differences, 

 such as a more primitive nerve-cord and alimentary canal, 

 are just those which might be expected between a larva and 

 its imago, Avhile the resemblances are very striking. Thus 

 the evidence from the external morphology and internal 

 anatomy is strongly in favour of the assumption, which was 

 so probably on general grounds, that the larva belongs to 

 Paracorotoca. 



VII. SPECIALISATION ASSOCIATED WITH THE 

 TERMITOPHILOUS HABIT. 



The structure of the imago and larva of Paracorotoca, 

 as far as it has been ascertained, has now been described, 

 and it is hoped that it will be possible for those who have a 

 wide knowledge of the typical organisation of free-living 

 Staphyliuids to form a definite opinion on the nature of the 

 modifications which have resulted from the peculiar environ- 

 ment of a termite nest. 



Some of the more obvious peculiarities may be briefly 

 summarised : 



