The Cane Grubs of Australia. 27 



from larger hosts as L. alboliirta or would the greater amount of nourish- 

 ment necessarily yield the females? We believe that this phenomenon 

 of the food supply regulating the sex of an insect, where great disparity 

 occurs in the size of the sexes, has been recorded by other writers. 



THE SCOLIID HYPERPARASITES. 



The Scoliids themselves are in their turn attacked by two parasites, 

 a coleopteron and a dipteron. 



MORDELLID Sp. C. 109. 



This little beetle has been recorded thrice as a parasite of the 

 Seoliida^. On December 1st, 1914, an adult emerged from a Scoliid 

 cocoon taken from a canefield ; on January 7th, 1915, a dead adult was 

 found in the host cocoon from canefields; on October 9th, 191,5, one was 

 bred from a cocoon of Discolia soror. An adult was captured on leaves 

 of sugar-cane, November 27th, 1914. At what stage in the life of the 

 Scoliid is it attacked by its parasite? 



BOMBYLID Sp. D. 22. 



This fine fly is common around Gordonvale in December, January'-, 

 and February, where it may be seen hovering over fields, roadways, etc. 

 It has been bred from Scoliid cocoons on the following dates : — November 

 20th, December 6th and 26th. The larva pupates loosely within the host 

 cocoon. Pup* have been taken from the cocoons in October. 



THE DEXIID PARASITES. 



Several flies of the family DexUdce are known to attack the various 

 Scarabieid larva ; a single parasite emerges from the host ; only Stage III. 

 has been found parasitized ; in most cases the host larva lingered on for 

 some weeks after the normal time of pupating before succumbing. None 

 of the flies are common, and the percentage of larvaa^ destroyed by them 

 is decimal. 



DEXIID Sp. D. No. 4. 



A dull species with bluish reflections that is often taken in summer 

 around the laboratory building. It has been bred on four occasions, 

 as follows: — From Stage III. Basygnathus anstralis, 18th March, 1915; 

 from puparium in black loam canefield, 18th March, 1915 ; from Stage 

 III. Dasygnatlms, 12th August, 1915; from Stage III. Anoplognaikus sp. 

 No. 686 found in yellow clay loam jungle canefield September 14th, 

 parasite pupated between November 24th, December 8th, emerged 

 December 19th, 1915. Thus the two known hosts are Dasygnathus 

 anstralis and AnopJognafhus sp. No. 686. 



DEXIID Sp. D. No. 23. 



A bright blue-green species, the abdomen partly black, that has been 

 noticed on tree-trunks in the forest and on fence-posts during November 

 and December. It has been reared on three occasions, and alwa3^s from 

 Stage III. Dasygnathus anstralis. The records are — Host found in red 



