99 



ON THE CHRYSIDES PARASITIC ON ODYNERUS 

 SPINIPES. 



Bt ELMBS Y. STEELE, Esq. 



Gentlemen, — I have been set down in our programme to read this paper 

 as a sequel to the account given of "Mason "Wasps and their Parasitic 

 Bees " in our Transactions of last year. The press of other occupations having 

 deprived me, at the proper time in the present season, of the opportunity for 

 pursuing further the study of these insects, I must depend entirely, for the 

 information I desire to give you, upon the observations of our friend Dr. 

 Chapman, who has kindly furnished me with the materials for this paper. 

 I am thus compelled to resign the pleasant honour of authorship into the hands 

 of one far better qualified than I am, as an experienced entomologist, and 

 as a most acute, diligent, and careful observer, for the accuracy of whose 

 notes, knowing him as I do, I am prepared to vouch. 



Before reading these notes, it will, perhaps, be desirable that I should 

 remind you that Odynerus spinipes is one of those mason wasps referred to ; 

 that it burrows in sandy soil wherein it constructs a series of cells into 

 ■which it deposits eggs, together with a supply of living food for the forth- 

 coming larvae. That the Ghrysididce are a family of insects, somewhat re- 

 sembling bees in outward appearance, though smaller in size and refulgent 

 with the brightest colours. That these latter propagate their several species 

 with the aid of one of the most curious of the many reEaarkable instincts 

 that are revealed to us by the study of entomology. You will find specimens 

 of these difi'erent insects with cocoons set up in the box which I hand round 

 for your inspection. Now I shall read from Dr. Chapman's notes : — 



Though the Chrysidida have long been known to be parasitic, any de- 

 tails of their economy that could be relied on for accuracy have been wanting. 

 The species of the genus Chrysis appear, so far as is known, to be parasitic on 

 wasps and bees. Chrysis ignita, the most abundant species of the genus, will 

 lay her eggs in the nest of almost any kind of wasp or bee to which she can 

 obtain access, and occasionally she visits the burrows of Odynerus Spinipes, but 

 the two species which arc specially attached to this wasp, -vfrhilst they have 

 not been recorded as accompanying any other insects are Chrysis neglecta 

 and Chrysis bidentata. These two are common wterever Odynerus Spinipes 

 abounds. Chrysis fulgida has also been recorded as attached to O, spinipes 

 but I have never met with it, and 1 suspect it to be the proper parasifs 



