OF NOBTHUMBERLAND AND DURHAM. 151 



GEiOJS 4. PASSOLCECUS, Shuck. 



1. P. monilicornis, Dahlb. Dahlb.. Hym. Europ., 1, 243; 

 Bold, Entom. Mon. Mag., IV., 226. 



Four males of this species, which is new to the British Fauna, 

 were taken entering the cracks of a gate-post, near Wallholme, 

 a small " town" a mile or two west from Grilsland. 



Genus 5. PEMPHREDON, Latr. 



1. P. liiguhris, Fab. Dahlb., Hym. Europ., I., 259, 159; 

 Smith, Monog., 175, 1. 



Common. Burrows in decayed wood, and provisions its nest 

 with Aphides. Male and female taken in copula in July. 



As showing that the last deposited egg is the first to be deve- 

 loped into the perfect insect, I may mention that I one day filled 

 a large quill with the pupae of this species, placing the uppermost 

 one at the bottom of the quill. On reaching home I found that 

 the warmth of my pocket had brought out a male from the lowest 

 cocoon in the quill, and in his endeavours to escape he had eaten 

 his way through more than a dozen of the other pupge. 



Genus 6. CEMONUS, Jurine. 



1. C. unicolor, Latr. Dahlb., Hym. Europ., I., 255, 155; 



Smith, Monog., 178, 1. 



Very common ; it excavates bramble and rasp sticks, provid- 

 ing its young with Aphides. 



2. C. lethifer, Shuck. Dahlb., Hym. Europ., I., 254. 154 ; 



Smith, Monog., 179, 2. 



Also very common, and of similar habits to the preceding. At 

 Benton it excavates the cut rasp sticks, which are used for tying 

 up flowers, for breeding in. 



