366 



Transactions of the Society. 



in this position throughout the latter's metamorphoses. Our 

 account, for the present, must begin with the larva in the later 

 parasitic stage of its existence, when it lies coiled up in the body- 

 cavity of the imago of the ant, from which it presently emerges to 

 lead a free existence in the soil. 



The larv?e grow to a length of 20 to 50 mm. before emercjing 

 from the host, and attain a diameter of " 3 to • 65 mm. During 

 the subsequent free existence some further grov/th may take place, 

 though the greatest dimensions here given for the larvse are greater 

 than we have actually observed in the adult. 



The newly-emerged larva has few characters which enable it 

 to be distinguished from the larvae of other members of the genus. 

 It appears, however, to be exceptionally short in proportion to its 



O! UlVh. 



Fig. 7. — Merinis myrmecophila. Head of adult female ; dorsal view. 

 I., lateral organ; ces., oesophagus ; s.d.p., subdorsal papilla of right side. 



thickness. The head- papillae characteristic of the adult are as yet 

 unrecoonizable. Of the internal organs little can be seen in 

 whole preparations owing to the great development of the fat-body. 

 In a series of sections through a larva still in situ in an ant it has, 

 however, been possible to establish the fact that internal genital 

 organs are precociously developed. This larva shows a long, strip- 

 like organ (fig. 10, t.) squeezed up between the fat-body and the 

 musculature on one side of the bod3^ and lying between the 

 lateral and tlie subventral fields. On examination with high 

 powers, this organ proves to be a testis, already containing numbers 

 of spermatozoa, apparently fully developed. The testicular tube 

 appears to be single, and, so far as can be judged from the sections, 

 it runs throughout nearly the whole length of the larva. A 



