102 ARKIV FÖR ZOOLOGI. BAND 12. N:0 15. 



B. Jaws slender, head much shorter, not twice as long as broad (Text 

 Fig, 55). M. parviceps Mjöb. n. sp. 



Distribution: S. Queensland. 

 II. Head large, jaws long and slender. 



A. Head twice as long as broad. ^M. serratus Frogg. 



Distribution: N. Australia. 



B. Head twice as long as broad, more rounded at the sides. 



1. Head reddish-yellow ; more rounded at the sides. 



M. excisus Mjöb. n. sp. 

 Distribution: S. Queensland. 

 (Text Fig. 57.) 



2. Head påle ochreous, not so much rounded at the sides. 



M. Tur ner i Frogg. 

 Distribution: Queensland. 

 (See Froggått, I. c, Pl. XXXIV, Fig. 8). 



Key 



io three hitherto known imagines of the Australian Microcero- 



t er mes species. 



I. Prothorax deeply excised in the centre of the bind margin. 



(Text Figs. 53 a, 56.) M. exisus Mjöb. n. sp. 



II. Prothorax not deeply excised in the centre of the hind margin. 



A. Head small, prothorax slightly curved in the centre of the hind 

 margin. 



(Text Figs. 53 b, 54.) M. parviceps Mjöb. n. sp. 



B. Head larger, prothorax not excised in the centre of the hind 

 margin. M. Turneri Frogg 



47. Microcerotermes distinctus Silv. 



This species is apparently closely allied to M. Biroi 

 Desn. and also to M. serratus Frogg. but differs in having a 

 longer and more narrow head and shorter and stouter jaws, 

 which are more sharply curved at the tips. My specimens 

 of soldiers from North West Australia all show these charac- 

 ters. Thence I have no hesitation in referring them to 

 SiLVESTRi's new species from S. W. Australia. It does not seem 

 to build a special nest, but forms simple galleries under 

 wooden pieces on the ground. 



Soldiers and workers taken in the vicinitv of Derby 



ev.»). 



